Category: Arduino

The 5th Sense

Story So Far: A lamp has been made, a hot plate has been made, some buttons have been made or bought, a clock and an LCD screen have been bought. All has been wired up and programmed. Just need to give it all somewhere to call home.
TL;DR: First and last two paragraphs are on the project/blog, just saying what casing situation is. Everything in between is beyond the realm of tangential and well into just plain irrelevant – why acupuncture works and why smells make for more potently emotional memories than other senses can come up with.

As I’ve mentioned somewhere before, this is a completely hand-built, bespoke alarm clock and has a right to be aestheticised accordingly. The proposed design is below; glossy white plastic casing and a wooden veneer finish on the top panel.  Unfortunately, to make that happen I need two things; the means to make those panels out of glossy white plastic, and the motivation to make an accurate sketch in CAD. Both of these things are beyond the horizon as I look through time from the present moment. Oh well.

Front and top view of proposed design. Tea should not be this colour.

In the meantime, there’s a pretty easy cop out. A base and four walls made from LEGO with a top panel made from an old floorboard. I like to think it makes up for being utterly tasteless as a piece of homeware by being a tasteful homage to the life-long engineering pilgrimage that has culminated in its creation – there’s something flirting with profoundness in the fact that the first project I’ve done as a qualified engineer is made from the toy that very probably predestined the entire journey. I think that whether the clock, in its temporary form, appears as flamboyant or garish really just depends on how camp the entire project is, on its ability to present itself immediately and unmistakeably as only having been created in the context of itself and the joy it might bring. Given that every post so far involves some sort of technical hiccup and a subsequent compromise, I’m not brimming with confidence that I have achieved good camp; it’s difficult to say exactly what camp is, but it certainly isn’t compromise1. It also isn’t a goal to be achieved and anyone who has ever made it so has failed before they start.

The “finished” product. More or less.

So, what hope do I have of having made something good here? Well, one place there has been no compromise has been these blog posts – self-indulgent and conceited, almost to an onanistic extent, with very little irony. Perhaps then, the project as a whole can be construed as camp, and thus, the clock’s physical form construed as intriguingly vulgar, rather than nauseating and garish. Probably not though. And in any case, my opinion on the matter is the least important of all. Regardless, the Teamaster 2000 blog series is ending with this post, only to be appended to if/when I feel like it. It’s been a good run but, as I have had other ideas, I have developed cabin fever with this project as a framework for my writing. There’ll be a rearrangement of the entire site soon to accommodate different subject matters. For right now though, here’s some unabashed nonsense. Enjoy.

Like for like, if you compare an adequately caffeinated human with a horse, it would be accurate, if a little unkind, to call the horse an idiot. One thing that humans and horses can both recognise though, is that the sensation of the individual sinews in your leg muscles morphing into wound-steel guitar strings that scour one another with each muscle contraction is a sensation that’s probably best avoided. Primarily because it hurts, but also because it probably means that you’re about to shred those strings. In a bad way. But, with modern medicine’s miraculous mastering of human physiotherapy and horse euthanasia, is the risk of catastrophic fissuring worth it? Picture the scene; you’re a delusional jockey. You know your horse is the fastest, you know it can bring home the win, you’re just worried that it might suddenly become aware of the fact that it is tearing itself limb from limb in the process and that that moment of hesitancy before you can whip some sense into the dumb thing will cost you everything. What can you do to prevent this travesty? Well, you could rub your horse with chili peppers. As luck would have it, horses can only feel one of either; a dull, persistent pain (muscle pain, mild headaches, crushing etc); or a sharp, momentary pain (burning, stabbing etc) at any one time. The preference, for survival reasons, goes to the sharp, momentary pain (we can afford to forget about dull aches for the duration of a short sharp pain, but not being able to feel short sharp pains in a place where you have a chronic dull ache might mean you don’t feel it when you get stabbed, or bitten by an insect). So, what’s that got to do with chili peppers? Capsaicin, the “hot” chemical in peppers, is perceived as hot because its chemical structure allows it to bind with the receptors we use to know if things are (thermally) hot. These same receptors trigger an almost identical response to that associated with physical pain and the neural pathways which light up because of heat tend to be of the variety that represents sharp, momentary pain – the same variety which overrides (in a sense, provides relief from) dull aches. So, hear me out; we rub this Stupid Horse up and down with chilis, emulating its immolation, the pain prevents the animal from noticing that it is utterly eviscerating its own muscles, it runs like a creature possessed and ruptures every fibre of its being in doing so, the capsaicin loses its potency, a muscular cataclysm surges through the beast, the on-site vet tells you how much a horse’s lifetime of ketamine costs, the prize money won’t cover it, horsey gets trolleyed to the Temple Grandin temple and they drive a bolt into its head, that night you drink from the winner’s cup and argue with a man in an alleyway about how much ketamine costs. A winner.

Hell of a proposition, and also the reason capsaicin is an illegal doping agent in equestrian sports. The whipping, which is not only legal but crucial, has a similar “numbing” effect though. This also works on humans and is the reason pre-match changing rooms for a variety of sports wreak of deep-heat, and also why acupuncture and massages make you forget about your chronic back pain2.

To my knowledge this Edna Milton quote is fictitious and Jockey Full of Bourbon equally so. It is entirely possible that this is not the case though.

I say all that to say that the science behind human senses is interesting and useful. I also say it because it’s rare to be in a social situation where I get the chance to. Anyway, the sense of touch/pain is fascinating of course, but the sense at the heart of this post is smell. This peculiar sense is uniquely poised to debase our rational-thinking cortexes and annul the “sapien” status we have endowed ourselves with. By this I mean a familiar smell is much more likely to trigger fits of pique than other sensations are3. To illustrate:

Cast your mind back to the last time you lost control – convulsive laughter, apoplectic rage, hysteric crying, etc, all just variations on a theme really. The theme being that even if God had given us free will, there’s still parts of us that have literally no concept of who the fuck we are and, as such, will never bend to that will. For most people, one such part is the limbic system, the captain of our emotions. Most interactions light up our whole brain and bounce around until they finally catch the attention of the cortex, the executive part of the brain, and the part where our sense of self is strong, in this way we can interact in a manner that is “in-character” for us. Some interactions though, make a B-line for our limbic system and before we can think about how we, our grandiose idea of ourselves, feel about something and then go about releasing chemicals to feel that way, our limbic system has already put in motion the production of the euphoric, aggressive, or depressive chemicals in our body. Things like somebody slipping on a banana peel, slapping us in the face, or mentioning a loved one will often trigger this kind of unconscious response. Also, things like smells. Turns out our olfactory system is uniquely linked to our limbic system, so that no matter who we are, or who we think we are, some smells will just make us feel things. Evolutionarily, this makes a lot of sense. People/proto-people who had an innate and immediate aversion to the smell of bear urine probably had a much better survival rate than those who’s biology allowed it to come down to personal preference. Although it is hard to imagine a huge difference between the two groups.

All sorts of things trigger a strong limbic system reaction, but not all of them end up with us curled up, cowering in the corner of the kitchen trying to remember the last time I cried like this? And is it usually this harrowing? And is it happening more often? Is it starting to define me? Did I see it coming? Can I see it coming? What if someone walks in? What if someone calls? What if this happens in front of someone? Is it over? That’s it? Well, okay. Maybe I’ll have a nap.

Well, the difference between a melancholy twang and an all out fit, is how capable your cortex is to retake/steer the reigns. This of course depends on many things, but the events that are truly capable of razing that little neuron nucleation point that endows us with “humanity” to the ground, are those that attack its foundations. The cortex’s entire métier is to rationalise the world through the sensibility of our ego. This allows it to do all sorts of things, most notably, predict the future (rightly or wrongly). Anyway, assuming my immediately-and-easily-proven-to-be-incorrect™ definition of it is correct, we can see that to sabotage our cortex there are two options. We can suppress our ego, which can lead us to be free of the pains of pre-cognition and prejudice and truly live in the moment (for some this is an intentional and spiritual ascent to the pinnacle of Maslow’s Hierarchy, for others, it is a symptom of their unintentional and hellacious descent to the opposite end), or, the world around us can become entirely unrationalisable. Focusing on the latter and circling back to the sense of smell, as you are no doubt attentively waiting for me to do, the memory of a smell can be pretty difficult to contextualise, and contextualising is a pretty big part of how we rationalise the world around us. For example, seeing a familiar actor in a movie, a world where you don’t know who she is doesn’t make sense, it’s irrational, but you just can’t quite say you fully remember her. So, you contextualise the faint memory of her by going to her IMDB and seeing that she had a cameo in Friends one time. The frosted glass you were viewing the memory through clarifies. You turn off the movie that you weren’t that invested in anyway and switch to an episode of Friends you’ve seen more often than your actual friends this past year. The world makes sense again3.

We primarily perceive the world visually, and so context for memories is often synonymous with some sort of imagery. When we encounter a smell and commit it to memory, we also store an image of the source of that smell as context for it. This is then our memory of that smell. But, as time goes on and you encounter the aroma again and again, produced by different sources and in different surroundings, it becomes decontextualised in your memory. So, when you smell cheap plastic, it may remind you of a Kinder Egg, or a ball pit, or a LEGO set. If you still encounter any of those three things on a regular basis, your brain will immediately associate the smell with that item, and you can picture it. If, however, you’ve stuck to the societal norms of growing up, it’s likely some time since you last encountered any of the worthless treasures of your childhood, and a whiff of their characteristic plastic will inundate your brain with a familiar fragrance and the feeling of contentment that you haven’t experienced since you were a child at play. Your head will spin as the scent flares up a limbic system emotional response and the absolute bewilderment induced by the lack of context will only amplify the emotions, your brain has absolutely no idea which visual memory to attribute to this smell and you’re in limbic limbo until it comes up with something. Eventually, when you really try to pin it down, you will come up with a specific ghost of your past to lament over, this is not to say that the smell genuinely most resembled that item, but more to say that you were thinking about that thing, or things adjacent to it, most recently and were primed to land on it.

Put all of the above together and you’ve got a mess of a blog post. Put the bits about olfaction together and you’ve got a sense that not only takes a shortcut not available to other senses to illicit an emotional response. But also, a sense that can make sure that response lasts. Not only has your nose got a head start on your rational brain, but it’s also tied your brain’s shoelaces together.

Confusion, nostalgia, smells – an absolute crisis.

It’s worth pointing out that there are also smells that actually do conjure up a specific image, like if you only ever smelled that weird soft-yet-abrasive carpet that has a texture somewhere between the two sides of Velcro when you were a child lying on the floor of your local library. When you’re hit with that scent anywhere else, it will likely conjure up an image of that weird blue-yet-grey carpet that is almost certainly made from old bus seats in a process that is disconcertingly similar to how pigs (presumably along with other animals) get turned into Billy Bear ham (not a sponsor). This scent may well cause an overwhelming emotional response, but this response is more akin to seeing an old friend than the previously described frantic scouring of memory banks for an image to provide context to a familiar smell.

I say all that to say that I was feeling overwhelmingly nostalgic when I used LEGO to build the casing for this alarm clock. I also say it because it’s rare to be in a social situation where I get the chance to. This post started as a commentary of my emotions and memories as I sat fulfilling a childhood fantasy; playing with LEGO by light of a head-torch, well into the night, cross-legged on the garage floor. But the narrative fell apart pretty quickly so I deleted it all and wrote the above. I’ll be honest, the entire build didn’t work out terribly well. It doesn’t look at all like I envisioned, and steel was a horrible material choice for the hot plate. The steel cuboid will one day be an aluminium (I think) cylinder, and the LEGO/floorboard housing will be superseded. That sentence might well be the full extent to which I write about those updates though. I still enjoy the thought of the build, but I’m over writing about it.
Thanks for reading. While I can’t give any timescales for anything, I can give some details on what the future content of this site will be. As you’ll have noticed, I have a penchant for biology, this will be developed on. I also intend to write short pieces inspired by other stories I’ve heard, either in books or in music or in some other form. As a special case of this I intend to make a page called “Helsabot Fanfiction”. “Fanfiction” here being very tongue-in-cheek.

A final, very imperfect photo.

1 – Please read Notes on Camp by Susan Sontag, a “paper” published in the 1960s. Very good read.
2 – I’ve got nothing against jockeys. Also racehorses are generally very well looked after and the events detailed are an exaggeration of the highest order. Horses were indeed “doped” with capsaicin so they wouldn’t feel pain, but if it would be possible for one to run so hard that it gives itself injuries that warrant being put down, I don’t believe so, but I don’t really care to look. I’m very happy to be naive on this issue.
3 – All of this stuff may be entirely wrong, at a high level and at a low level. It’s all accurate as far as I know, but I have a chronic and severe case of Dunning-Kruger-itis.

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What All the Howling’s For

Story so far: Key components are working; hot plate made from steel block and lamp made from . . . lamp?                                                    

TL;DR: My Clock tells the time to my Arduino which tells it to my LCD Display. The technical lingo for this communication system is . . . curious. Clocks work by counting how many times a crystal vibrates, your dog can hear the crystal vibrating and hates you because of it.

There’s just three more bits of this build to tackle – the Clock/Display, the housing, and the code. This post will cover the Clock/Display – that’s why I listed it first. I’ll start by saying that the terminology for how the Clock and Display get wired up is one of the more curious examples of engineers anthropomorphising their hardware, presumably in lieu of friends (as per this entire blog series). The picture should make it clear what I’m talking about.

A model for “I2C” communication. Arduino “master” can communicate with its “slaves”, the Clock and the Display, through the red data line.

Yep, we don’t just have a controller and its peripherals, we have a master and its slaves. I regularly think about how that ever became the accepted nomenclature and am yet to make it past the incredulity of asking “How’d It Get So Scandalous?”. But Stay Woke, there’s a few examples of leaving these terms behind, most notably, the Python programming language now refers to “parents” and “workers” instead. Personally, I don’t see anything inherently egregious about the terminology, I just find it incredibly strange that those terms were the ones that stuck. It’s also worth pointing out that any brands that have changed their vernacular seem to have done so as a result of the same single court case in Los Angeles. So, while it’s easy to assume that complaints are a result of forcing the wrong context onto the situation, the aforementioned single court case may be a result of a single particularly flagrant use of the terms.
The rest of the story is oh so very L.A. too. I put it to you that nowhere else on the planet would a complaint centred on an African American person feeling offended at the use of the term slave be countered by a complaint centred on a person involved in “the BDSM sub-culture”, who feels offended that someone feels offended at the use of the term slave (presumably outside of certain contexts). But that’s what happened. Among other things.

So, anyway, how that circuit works – the Arduino master shouts the address of the slave Clock down the red “data” line to tell it to listen up, and then asks it for the time. The Clock obliges and sends the time over the data line to the Arduino master’s address. The Arduino master then shouts the address of the slave Display down the data line to tell it to listen up, and then tells it to display the time. The Display obliges.
The blue “clock” line is just used to keep everyone in sync and has nothing in particular to do with the actual Clock, or anything I feel like writing about, really.

Aside: The Display is blindingly bright and so it will be asleep most of the time. Subsequently, I made a touch sensitive button to wake the Display, but I don’t think I could write anything about it that I would ever want to read. So, I won’t write anything about it.

There is one more vastly interesting topic that has a place in this blog post, however, and that’s the Clock itself. How does it know what time it is? The method below is true for pretty much any clock that has a battery or other electric source1 (including your phone1, watch1 and microwave).

The functional part of the Clock is a little tiny quartz tuning fork. A tuning fork is just a tool that vibrates at a specific frequency when you hit it – when it vibrates at a specific frequency, that creates a sound of a specific pitch.
The quartz tuning fork in your battery-powered watches and phone is set at a frequency of or above 32,768 Hz – too high of a pitch for you to hear (also too long of a number for you to read, I’ll say 32K from now on). This makes sense, I mean, if I wanted to hear my phone make a high-pitched whine all day, I’d call my girlfriend, am I right fellahs? Ha. Got ‘em. Nah that’s a joke, I don’t uh have one of those, like, you know, a girlfriend, or whatever.

Notably though, that frequency (32K) is about the same as an average dog whistle, so keep that in mind the next time your dog seems a little restless – your watch is like a very whiny fly buzzing around their ears1. This is another classic pitfall of anthropomorphising things – forgetting that humans and animals perceive the world very differently. I still wouldn’t worry too much about it though, I can’t imagine the noise is very loud. It is certainly audible, though, otherwise we wouldn’t have bothered to design these things to vibrate at a frequency we can’t hear.

“Artist’s” impression of a dog being bothered by a particularly irritating vivified watch. For commissions email contact@calebhalfpenny.com. 😉

Anyway, the important part about these quartz crystals isn’t that they make sound, it’s that with each vibration, they also generate a small pulse of electricity. Since this pulse of electricity happens every vibration, and we know there’s 32K vibrations every second, we know we need a circuit that adds one second to the time for every 32K pulses we put into it. If that sounds like a fun thing to learn about, you can go search for info on “edge-triggered flip flops” – be warned though, despite their name, they’re no day at the beach. Unless you already have a grasp on binary signals2.
So all we do is give the Clock a starting time, AKA setting your watch, and start it. It’ll then count from 0 up to 32K over and over again, and every time it returns to 0, it’ll add a second on to the time. Then there’s a whole mess of gears and/or circuitry that keeps track of how to display that as minutes and hours. Truly though all the Clock is doing is counting how many seconds have passed since the time it was set. And THAT’S THAT.

Except for the most interesting part! When we hit a tuning fork, the noise eventually fades to nothing. A similar thing happens with our electrical pulse from our quartz tuning fork. So, we need to keep hitting it. Except we don’t. We don’t hit it at all. We actually zap it with some electricity because in a similar way to how our quartz crystal produces electricity as it vibrates, zapping it with electricity makes it vibrate.
So, we start by zapping the crystal with electricity to make it vibrate, this gives us the regular pulses of electricity that we’re after to keep track of the time. The clever bit is that we also tap off a little bit of that electricity and amplify it, then zap the crystal with our amplified electricity to keep it vibrating at the right frequency. If the ability to understand a quartz crystal clock circuit was the only thing that came from my engineering degree, it’d probably still be worth the fees. These circuits are what make me tick. Ha. Got ‘em. Nah that’s a joke, I don’t uh have one of those, like, you know, a way to pay off university debt, or whatever.

Left: Here’s one I made earlier. An uncovered quartz clock from an old phone of mine. Pretty cool.
Right: A very questionable illustration of the time-keeping circuit. When a small electric pulse is given to the amplifier by the quartz, the amplifier allows a large pulse through from the battery to sustain oscillation of the quartz.


The concept related to quartz producing electricity as it vibrates is called piezoelectricity3. Pronounce that literally however you want to whenever you say it out loud, just do it with conviction. That’s what everyone else seems to do. Resonance also has a pretty big role to play in all this. It’s a cool thing.

That’s about it, now we have a circuit where the Clock is constantly counting the seconds and telling the Arduino the time, and the Arduino is constantly telling the LCD Display to display that time, but the Display can’t actually do that unless I touch a button to wake the Display.
Also, if you lose your dog whistle, hold your watch up to a microphone4. Also, also, don’t kink-shame.

  1. Except that I make a lot of reference to the 32 KHz type of crystals. These are very common, but for something like a phone or a smartwatch, the crystals actually vibrate at a much higher frequency. Generally, this means the tuning fork can be made smaller, leaving more space for an extra camera lens or something that can be marketed better. The rule of thumb that I have completely made up is that if you can reasonably say that something is a computer, it probably doesn’t use a 32KHz crystal (and a dog probably can’t hear it).
  2. Each flip flop changes state only at the rising edge of its input. This way, each flip flop outputs electrical pulses at half the frequency of the input. Halve 32,768 Hz fifteen times and you get a frequency of 1Hz – or the frequency of a clock’s second hand.
  3. Piezoelectricity isn’t my forte, but, as I understand it, the crystals get designed so that some inner structures are positive and some are negative. To the outside world these charges balance out so we don’t get something like a battery or a metal. But if we deform the crystal (by hitting it or electrocuting it), these inner structures shuffle around a bit such that the charges are imbalanced in some areas – electricity is made. I think.
  4. This won’t actually work. Microphones are typically designed to only pick up signals that humans can hear and even then they often miss the higher frequencies. I only say this so you don’t think your dog is being deafened by a person holding a microphone in their left hand.
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Do You Have Ppe for Drilling Steel?

Story so far: The light circuit is working, so I can simulate a sunrise. The tea-making aspect remains to be seen to.

TL;DR: I drilled into a steel block and put a cartridge heater inside, the block is now a hot plate.

Following from the flaming failure of a first foray into hot plate building, a complete rethink was thunk. Now, I shall simply drill a hole into a steel block and insert the cartridge heater. The heater can do its thing until Tha Block is Hot and then the block can heat a cup of tea for breakfast. Seems reasonable?

The first step is to drill a cartridge heater sized hole in a steel block, that is, drill a cylinder of about 0.5cm diameter and 2.5cm depth. For reference, imagine a standard antibiotic pill in your hand, you know, half red, half yellow capsule full of feel-good, perfectly reasonable to be swallowed whole, as per its design. Now imagine the obtrusively sized, obtusely designed choking hazard that it morphs into the moment it leaves your sight and enters your mouth; that’s about the size of the cartridge heater.

A steel block and small heating element
The drilled hole and the heater, both lined with thermal paste.

Drilling a hole that size into steel with a hand drill is no routine procedure. Learning the correct method required substantial trawling through the unchartered waters of random forums and subreddits, where each comment further verifies the Big Fish Theory; expert metal workers are exposed as mere novices by increasingly snide remarks of “Um, actually…” that are as lacking in self-awareness as they are in relent – at least until someone mentions Hitler. Unsurprisingly, the omnipresent Mariana Trench of knowledge, YouTube, was also explored. One of the titans of the platform, Gus Johnson, was there to provide his trademark well-founded, rational and at times even cheekily comical interpretation, just as he has done for the trials and tribulations of the working man in America; the toxic lack of empathy that infects the landscape of Google reviews; and the decaying state of our natural world as we stray further from God. The video I speak of, though, is of course “Gus Johnson Sings an Entire Conway Twitty Album”.
Bus croons:

You want a man with a slow hand
. . .
You want somebody who will spend some time,
 Not come and go in a heated rush

This pretty much sums it up. If you use a very high speed, you’ll initially drill through by scraping lots of very fine steel filings away, however, eventually you’ll end up with a thick, impenetrable layer of these filings at the bottom of your hole and all you can do is move them around and get them into a heated rush – blunting your drill bit in the process. What you want to do is keep the rpm low and apply as much pressure as you can downward through the drill bit. You’ll know you’re Doin’ it Right when the steel you’re cutting away starts to slither up the thread of your drill bit as continuous and spiralised serpentine articulations – acquiesced entirely to their charmer.

It really does require you to spend some time with it, baby. The hole I drilled took around 2 hours and it wasn’t light labour either! At first, I tried summoning every ounce of force I could muster from my arms and pushing down on the drill, whose response was to summon the spirit of Laura Les and subject me to the harshly shrill, yet somehow enchanting dissonance of the bit turning in place fruitlessly – thus reminding me that my arms are indeed like very roast-able little cigarettes. Ultimately the only way I could pile enough force behind the cutting edge of the drill bit to make it carve through the steel was to lie myself atop the heel of the drill and push my weight through it. While this was effective, every force has an equal and opposite reaction, and here I am pushing down through my sternum with enough force to continuously carve steel. You’d think with a name like sternum it’d be made of sterner stuff but turns out this process got pretty painful pretty pronto. So, if you ever want to attempt something similar make sure and check the checklist below.

PPE For Drilling Steel:

  • Goggles (Fine particles and smoke from burnt lubricating oil are both pretty bad for your eyes.)
  • Gloves (Brushing away metal swarf with bare hands is pretty much the exact same as rubbing a cheese grater.)
  • Chest Cushion (Place between sternum of driller and heel of drill to avoid bruising your chest the way you did after watching Tarzan for the first time.)
Some drilling equipment
The required PPE, plus a good example of the fine swarf you want to avoid creating. You can’t avoid it entirely. Bonus: Always have a hammer on hand.

Of course, all that list protects is your body and the many emasculating mistakes made along the way raise the question: Do You Have Ppe for Self-Esteem? Well, personally, I vacillate between immersing myself in music where I can imagine myself as the audacious and brazenly immodest protagonist and lamenting over music where I can think, “well, at least I’m not that guy”. Each the type of music that concerns itself so singularly with one pole of the human experience, disregarding disaffirmations so indiscriminately, that to tell someone you enjoy it is to sully their notion of you with an apprehensive perplexity regarding the lucidity of your perception.
Music to count marbles to for those who don’t get it, music to hide marbles to for those that do.

Anyway, that’s the heating block done, in a very uneventful series of events I coated the heater in thermal paste and shoved it into the hole then turned it on. The block got very hot and all seems good. Onwards.

A cup on top of a steel block
The “finished” product. If you’re thinking “wait that block is far too big for efficient heat transfer!”, you’re right. I’ll address it when I’m good and ready to face up to my mistake.
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Turning on the Bright Lights, Part Deux

Story so Far: See Story so Far and TL;DR sections of Part 1.

TL;DR: My circuit needs another resistor or it will continue frying everything. It claimed another few victims before I realised this though.

After the traumatic experience it had endured I decided to give the laptop a break for a while and instead maybe check up on my circuit wiring. We were well into the evening now and the garage was engulfed by the umbra of the garden hedges, but I had been using the head torch all day, so had to switch it to the dimmer mode to save energy. The dimmer works exactly how I described dimming LEDs in “The Impossible Dim” except badly done whereby the flicker is pretty noticeable, giving a slight stroboscopic effect. It was annoying, but still better than being stuck in the dark before I finished. I rewired my circuit and gave it juice, same problem as in part 1, light comes on but just stays at full brightness. I had pretty much exhausted my troubleshooting list at this point, so I let the lamp stay on and willed the problem to make itself known. The “warm” white lamp really gave a much more homely feel to the workstation than the migraine inducing “Transfiguration of Christ brilliant” white headtorch LEDs.

The cooker hood bulbs being used in the lamp meant it gave off that special hue of light that is enriched with nostalgia. Nostalgia for all those nights having went straight to hurling training after school and arriving home battered, bruised and seeking comfort. Finding it wrapped in foil on the stove top. A home-made dinner that had watched on while everyone else enjoyed their meal and discussed their day; during post-dinner clean-up it was lovingly wrapped up in foil so as to capture a healthy serving of the Family Table spirit under there with it. Then as I land home, I am welcomed by the working-class cloche basking in the warm glow of the cooker hood bulb; a glittering, scintillating treasure trove. I approach the light through the darkened kitchen, with each step forward my shoulders bob up and shrug off more of the day’s tension, and with each breath inward the scents of the kitchen build hope for what might be waiting. I reach the stove. Quick breath in. Hold it. Lift the foil . . . pork chops. Stuff that I’ll have porridge.

Yep, the light being given off by the bulbs was lovely, but I wasn’t so keen on the smell – the smell?! . . . suddenly the illusion of homeliness came crashing down as the scent of melting plastic made itself known. I glanced down to the workbench and the strobe of the headtorch made the pixie smoke1 cast a large, jittery shadow, giving the illusion of a much larger plume of smoke billowing out than there was. I’ll blame the ensuing overreaction on that.

I immediately switched the supply off and for absolutely no rational reason whatsoever began ripping my circuit apart. I believe I believed I was protecting the components from being harmed by the now disconnected and harmless power supply. All very silly behaviour. The only component really in use was the FET (the “dimmer switch” that the Arduino was supposed to be controlling). Now, there’s a couple of conditions where a FET will get very hot inside and try to get rid of that heat through its back panel; I had created one such condition2. To get rid of dangerous levels of heat the small back panel of a FET often requires a larger heatsink3 stuck on to it, I didn’t have such a tool attached, that is, until I tried to grab the FET and disconnect it. At that moment, my hand became the additional heatsink and the FET did its utmost to utilise it, sending whatever heat it could into my fingers. Very painful. Very very stupid. Very very very educational.
So, in summary, things fried in an attempt to build the simplest part of this alarm clock:

  1. Laptop’s USB port
  2. FET
  3. My fingers
  4. My brain
  5. Voltage regulator chip on the Arduino

The last of which was what had actually been producing the pixie smoke earlier. It takes the 12-Volts from the supply and steps it down to 5-Volts for the bits that like to work at 5-Volts. The only one of which I was using at the time is the pin controlling the FET. I had pretty much shorted said pin to the ground which meant it was trying to draw Unlimited Power (infinite current more specifically but Star Wars). That power was (obviously) too much for the wires in the voltage regulator to carry so they started trying to get rid of it by heating up their plastic casing. Which melted.

Slick patches on “AMS 117” chip are the bits that melted especially well.


The fix is very simple; add a resistor to the wire. All this is like dropping a watermelon off a 45-metre tower. As it falls it will get faster and faster, creating self-destructive carnage when it lands. Adding the resistor is like giving the melon a parachute, it limits the amount of speed the melon can gather on its way down to the point where you can drop it all day and not see red.


My short-sighted shorting had one more side effect; it had actually caused a failure inside the FET which meant it no longer operated as a dimmer switch and instead had become just a lump of metal, or a dimmer switch stuck at its maximum brightness4 hence the issues I was having. I suspect things got quite hot inside the FET and some tiny bits melted together, only to be cooled down by passing their heat off to my fingers.


After making sense of everything I ordered a new Arduino and repeated the experiment, now incorporating an appropriate resistor and new FET, the lamp works perfectly, dimming and brightening at will.
Incidentally, I referred to the Arduino as an “Uno board” in early blog posts, said posts were written before this Series of Unfortunate Events, at a time when I was using the Oosoyoo Uno (a knock-off of the Arduino Uno) which now, as you know, has a burnt-out voltage regulator. After the events detailed above, I figured I’d like to splash out on the real deal Arduino model. Started From The Bottom Now We’re Here.

1 – See previous post “Mouth Function Malfunction” for etymology of “pixie smoke”. Suffice to say it’s a quirky term for smoke from electronics.

2 – FET == MOSFET for the sake of this blog. My FET wasn’t for microcontrollers – the gate voltage should have been much higher than 5V to fully turn it on. Since I was only giving it 5V it was only partially turned on and still had quite a large resistance. Thus it was a resistive heating element, melting itself and giving off heat. It is now switched out for a “logic level” FET. 5V turns it on all the way – assuming my pwm frequency isn’t ridiculously high, apparently this can lead to the gate not having time to fully activate every cycle.

3 – A heatsink is just a block of metal that absorbs heat from a component faster than the air around that component can. It then has a large surface area in contact with the air to pass that heat on to the environment effectively. It then keeps on wicking heat away from the component. The more surface area exposed to air it has the better at its job a heat sink is – this is why they almost always have a finned design.

4 – I know that’s not quite right as the FET isn’t a dimmer switch in the classical sense (a potentiometer) but it’s accurate enough. More accurately the FET became just another bit of wire in a circuit with a 12V source (wall wart) and a 5V source (digital pin) powering 2 LEDs.

Just a reminder this is what the end circuit will now look like. Except the pins aren’t accurately labeled and there’s a grounding wire omitted. I think the omitted wire is superfluous anyway though.
1

Turning on the Bright Lights, Part 1

“Turning on the Bright Lights, Part Deux” is also live.

Story So Far: Heater prototype didn’t work, waiting on alternative parts. Playing with using pwm (unimportant technical term) to control some LED bulbs for the lamp.

TL;DR: I set up a dodgy circuit to test the lamp part of the alarm clock. Plugged said dodgy circuit into my laptop and gave the PC a fairly debilitating case of agoraphobia. Shock therapy not advised.

I think experimenting with the lamp made for a high-octane chain of disasters so I think I’ll use a sort of dramatic retelling to detail how I transcend the limits of my single-headed human form to fit so much stupid in. How Does That Grab You, Darlin’?

While waiting on new parts for the new heater I figured I could work on the lamp, this would have to be addressed at some point anyway and it would be a nice proof of concept for the heater circuit as they are identical in all the ways that matter. So, out to the garage I went, full of misplaced complacency and bright ideas about this lamp. I set up a very simple circuit1 which is stylised to be even simpler below.

Left: Stick person controls dimmer switch for light bulb, powered by car battery
Right: Arduino controls current flow through a MOSFET (3-legged box which I forgot to label) to control the lamp circuit, powered by 12V supply


After having set up the hardware I had to tackle the minor issue of the software; just a little bit of code to make the lamp brighten/dim brighten/dim repeatedly. My laptop had been enjoying a well earned rest up until that morning – it’s a coin toss between it and the kettle for hardest working appliance throughout my final year of uni – nonetheless it sprung to life right spritely like and was ready for a new project; like an over-zealous sheepdog pup; keen to impress.

Brightness of the lamp is on a scale of 0 – 255 so I set about writing code that would peruse said scale up and down at intervals of 5, updating every second.

Once the code was written, I began uploading it to the Arduino. The Arduino blinked intensely and thoughtfully while it tried to comprehend its instructions and commit them to memory, then, once it felt it had a grasp on them it returned to its steady state; a bright-eyed thousand-yard stare2. This vapid expression concealed a mind that was furiously rehearsing the instructions which now constituted its entire raison d’être. The only thing that could interrupt this fervent meditation was the command to effectuate these orders and begin actually making the world a brighter place – just waiting on the word “GO”. Like a well-disciplined (read indoctrinated) soldier, not yet jaded by combat. The word “GO” in this case was me hooking the Arduino up to the big ol’ 60-Watt power brick. Using a 60-Watt supply to run a circuit this modest is a bit like using a forest fire to dry your hair but I’m told that the Arduino knows exactly how to keep its distance and not get set alight so I went ahead and gave the order anyway.

Turn on the Bright Lights


The lamp came on immediately when connected and was beaten only by my celebratory smile for brightest thing in the room. However, for every second that passed without the lamp getting any dimmer, my expression picked up the slack; finally my face was furrowed and frowning in equal measures at the failure. My first guess was that there was a bug in the code and the brightness level wasn’t updating as it should. So, I opened the laptop and started rewriting the code in a more obvious, less succinct way. Just by habit at this point I had also disconnected the lamp from the Arduino.

At this point I had both the big ol’ power supply from the wall and a USB lead from my laptop going into the Arduino and as I reconnected the lamp circuit it came on with that same, persistent full-beam of failure . . . the garage didn’t seem all that much brighter. Not metaphorically or anything. It was because my laptop screen had gone to sleep at the same time. I hit the space bar a smack to wake it up again (and perhaps vent some anger at my incompetence), but the screen remained black. Interesting. Immediately I ripped the USB lead out from the laptop. Intuitive. I turned all off and began CPR on the laptop. On-button compressions triggered a gasp of air through the fans but it still remained unresponsive, after 40 minutes of poking and prodding we had him back and fully lucid. The diagnosis was that a rush of current from the Arduino into the laptop’s USB port triggered some sort of safety feature that protects the motherboard; this feature cuts the machine off from the outside world until a certain secret knock on the power button lets it know the coast is clear. While researching it I discovered “USB killers”; pen drives that when plugged in, give a massive shock to the motherboard to try and fry it and brick the target machine, honestly, that’s their only purpose – a perfect, pocket-sized example of man-kinds malevolence. I’m glad they exist though because if they didn’t the safety feature I triggered might not exist and my laptop could very well be toast right now.

“Turning on the Bright Lights, Part Deux” is now live to conclude this part of the build.

1 – If you’re technically inclined, the actual circuit I ended up using is drawn and carelessly discussed below. In the picture of the physical circuit up above though you can see I only have one resistor in *spoiler alert for part two* it’s not the important one.
2 – Arduinos actually do have an LED that blinks while they load up with new instructions and then switches to a fixed on state to show it has accepted the new code. This isn’t just me rambling. Let me try again. This isn’t just me rambling.

Probably the final circuit schematic

Blue box = Arduino
Red box = MOSFET
Basically Vin will put 12V across the LED light when the MOSFET is set as a short circuit. The MOSFET will be set as a short circuit when its gate pin has a voltage applied to it (when pin D2 is high [It won’t be pin D2 in reality, it’ll be one of the pwm pins to allow variable brightness]). There’s a 10 K-ohm resistor from gate to ground on the FET to avoid floating states. The two 220 ohm resistors are just current limiting resistors. D1 will be polled continuously, if the button is pushed, D1 receives a signal from the 5V rail and the Arduino toggles the state of the lamp (fully on/fully off) as long as it isn’t already in the middle of brightening the lamp for the morning routine.

1

The Impossible Dim

Story so Far: Original heater concept is a no-go as copper tubing can’t absorb/hold/make use of enough heat. Currently awaiting steel block as alternative. Sunrise lamp is unaddressed as of yet but parts are present.

TL;DR: Digital screens let you keep writing when there’s no space left, this can get messy. Digital screens flicker but our brain blurs the world around us to suit itself. Time is pretty crazy, right?

Notice: This ended up very long and took an age to write. Future posts to be planned out better and split into smaller, more frequent ones. Just a bit carried away with the subject matter is all.

Ever tried to take a photo of a digital screen? How come your eyes see 08:20 but your photo is just a blank screen? Or how come there’s black lines going through your photo of a TV screen? Well, Let Me Blow Ya Mind. And also take a meandering route to explain how I’ll make “non-dimmable” bulbs dim/brighten. Basically, a digital clock works like:

>>Check time

>>Clear screen

>>Reset cursor

>>Display time

>>Repeat forever [Forever ever? Forever ever?]

Clearing the screen is absolutely essential every time in case the time changes – if you try to write a 7 in a position where there’s an uncleared 6, it’ll end up as an 8; eventually the entire screen will just read 88:88 forever and this broken clock won’t ever be right, never mind twice in a day.

6+7=8

Resetting the cursor is another crucial part, it’s the same as pulling the carriage return lever on a typewriter except there’s no satisfying mechanical process or rewarding ‘ding’ to announce to the world that you have crafted yet another page-width of art. Typewriters also include a lock that prevents you from typing on at the end of a line and ensures you actually hit the carriage return lever, without such a lock us idiot humans would likely try to type on at the end of a line and shift the carriage to the left one too many times. That would fling the carriage from the typewriter, casting it out of its homely cradle and into oblivion and you better believe it won’t go quietly either, dragging your page of so-called art with it – a spite-fuelled punishment for your ignorance.
Now the type hammers will still strike the ribbon and stamp out their impression in thick, black permanence but there’s no paper to print on. And so, the letter-shaped manifestations of viscosity are projected into the wind, at the mercy of Aeolus. At their most ruinous these letters may land on a nearby book and construct upon it destructively, ruining the literature’s original meaning. At their most harmless, they may land on the reem of paper next to the typewriter, attempting to author a composition of their own.

Point being, digital screens don’t have such a lock. If you attempt to keep writing after the end of the screen is reached, the program will just throw the letters wherever it pleases. Their new allocated address could represent a random spot on the screen, which isn’t so bad, however, if the program is feeling especially malicious it could write them to a part of the memory which houses something important. Something like how long I want the program to run the heater for – for obvious reasons, this would be a disaster*. So it’s important to reset the cursor to the left [to the left].

The problem created by all this is that digital screens spend a not insignificant amount of time not displaying what they’re supposed to be displaying. Cameras with a high enough shutter speed have a fair chance of catching the screen while it’s blank or in the middle of being populated. TV’s do something similar but split their screen into smaller, more manageable horizontal strips and refresh each of them with their share of the next frame. That explains why TVs can appear to have black stripes across them in photos. I’m pretty sure there’s more at play than that but this is where my interests end with it for now. How come we don’t see screens refreshing with our eyes? This is the interesting bit, it’s also where my writing gets a little scatty because I’m overwhelmed with the implications of the topic, I will return to this topic with a more coherent narrative some day.

Gamers will know that humans view the world at about 60 frames per second** – that is, our brain takes a sample of the landscape of light around itself, using our eyes, every 60th of a second (Not quite true, see**). This is fast enough to make us think we’re seeing everything, all the time. Yet we don’t see screens flickering on and off all the time. Well, the screens flicker much faster than every 1/60 seconds and when that happens, all the things in between our samples ‘blur’ together. You can demonstrate this with your phone – decrease the shutter speed and photos can be made to appear blurrier, which is useful to capture motion, blurring something moving fast or blurring the background to convey movement in a still image is no doubt something you’ve seen and appreciated before.

Slideshow: ‘Sea’ the effect of decreasing shutter speed while photographing a video of waves. Longer exposure time means more of the frames blur together and the sea appears smoother/calmer (picture 2 vs. picture 3). Picture 1 shows a very fast shutter speed capturing the horiszontal lines of pixels which are being cleared/altered to show the next frame. Picture 4 shows what happens with a very slow shutter speed. Too much light is blurred together and it just appears as a bright mess.

So, when a light (or screen) flickers on and off faster than 60 times per second, the in-between bits blur together.*** For example, if you flicked a light on and off very quickly, your brain would blur the on and off states between samples and actually see a light that was on all the time but only at half brightness. Similarly, as long as a screen displays what it’s supposed to most of the time, that’s what you’ll ‘see’. This is very useful. See, my LED lamps which I want to use by gradually brightening them, mimicking a sunrise, well, they state explicitly on the box that they are “non-dimmable” – which also means they are non-brightenable; bummer. However, by switching them from full brightness to zero brightness very quickly I can make sure they blur to look like they’re at a certain in between brightness. By varying the ratio of the time the bulbs spend fully on to the time they spend fully off (duty cycle for the initiated), any brightness can be exhibited – assuming the bulbs are observed by a human. Of course, I can’t do this manually but my Arduino, which controls the lights, can flicker them for me very quickly – quite possibly up to millions of times per second if I ask it to. I believe it switches them a few hundred times per second when I don’t make any special requests though and that’s good enough.  A good camera might have shutter speeds fast enough that when it snaps a picture of my bulbs they will only ever appear as either fully on or fully off, with the probability of each varying based on the duty cycle. The brighter the bulbs, the more chance of snapping a shot of them fully on****.

It’s pretty crazy that we only observe the world at 60 frames per second, but imagine a world where we truly saw everything in front of us all the time, a world where we didn’t blur the in-between bits. Just a petrifying amount of information at all times entering our brains through our eyes – you would essentially be viewing the world in slow motion. But you still wouldn’t be able to think any faster – birds see in “slow motion” so they can observe and dodge obstacles while flying all gas no brakes style, for us slow-moving humans though, it isn’t really that useful of a tool.
It’d be pretty cool if we could give ourselves an adaptive shutter speed by blinking though and process visual stimulation as we see fit – slow our perception down when driving at high speeds, speed it up when looking at something frighteningly chaotic but harmless – could turn a flashing light into a constant light and avoid photosensitive epilepsy incidents. This would mean blinking 59 times a second to match our current speed of vision, however. Still a nice thought experiment.


Still, the prospect that the “shutter speed of your eyes” determines your perception of time is a very interesting area, particularly since it varies from person to person naturally – research is also trying to pin digital screen use to slowing down our shutter speed – it’d be interesting if that has anything to do with other research claiming reaction times are getting worse since digital screens became so commonplace. The technical term for the “shutter speed of the eyes” is the “flicker fusion threshold” or “critical flicker frequency” by the way. I’ve only just been introduced to it while researching how my LEDs worked for this very blog post but I am enamoured with the concept. Once I make it through a few papers/articles/videos on the topic and finish writing about this alarm clock project you can bet there’ll be a full-on post based upon it. I did say in a previous post that I would find a better, more abstract way to discuss people’s unique perception of time and a story loosely based on flicker fusion thresholds might be it. It does beg the question “what about blind people?” but I don’t have the answers to that yet. Obviously, optical stimulus isn’t the only thing we react to and gauge time from but it is pretty intrinsic to how we (people privileged with the sense of sight) perceive the world.

Food for thought: Higher shutter speed means less light enters the lens to be blurred together. Perhaps a lower critical flicker frequency (shutter speed) means observing the world as a more vibrant place with more light in every frame. Conversely, a higher value means a dimmer world view – flies have a critical flicker frequency 4 times that of humans – is that why their eyes are made up of so many lens-like panels and bulge out? A complicated biological balancing act?

*I’m not sure what exactly happens when writing to addresses that don’t exist, but I’d be confident it’s at least theoretically predictable. I feel like all memory is fair game but maybe not. Might be conflating using pointers and addresses cautiously with writing to peripherals cautiously and that might not be accurate, I’m not sure, but I’ll err out of apathy and err on the side of caution.

** 60Hz is troubling. I don’t think we actually sample our environment at 60Hz. I think we actually sample at 25Hz but certain other quirks of the optical sensing system make it appear as 60Hz. The entire scientific field is insanely complicated, what I’ve said would hold water in a conversation but keep an open mind to people expanding on/correcting it.

***Things might need to flicker faster than just “faster than 60 Hz” I think. Pretty sure Nyquist-Shannon sampling theory would come into play meaning for proper blurring to take effect it would need to be 120Hz – but also the 60Hz figure may take that into account, from context I think it does.

****I realise I’m talking about using pulse-width modulation as if I’ve just discovered fire but I’m trying to convey just how cool it actually is when you don’ take it for granted.

1

Mouth Function Malfunction

Story so Far: Alarm clock build parts arrived, currently experimenting to get the heater part working in order to prepare a cup of tea. A cartridge heater being used to heat copper tubing which is spiralled into a hot plate is the current technology.

TL;DR: I tried using the copper spiral as a hot plate with wood around it to insulate. The wood caught fire. I tried without the wood, the heater got aggressively red hot. I conclude that I want more thermal mass – ordered a block of steel into which the heater can be inserted.

Test number 2 of the prospective heater set up was a resounding failure. I had the heater inserted into its cradle and a metal cup of water placed on the copper spiral of a ‘hot plate’. Before testing though I figured the near-constant draught in the garage might become a problem. My thinking was that while heat should find it easiest to move from the copper into the base of the metal cup and heat the water, a constant flow of cool air around the heating set up will absorb a significant amount of that heat. To limit this, I surrounded the heater in wood; now the heat had two options for where to go: a metal cup or a wooden block; in my head this was a no-brainer . . . my head is a no-brainer.


I plugged the heater in and flicked the switch. “Hmm nothing’s happening, well, presumably the heater is working away, and I’ll just keep my ey – something smells good; like Christmas – no, something smells bad; like a burning project.” Something like that went through my head as the scent of pixie smoke and crushed dreams began to fill the garage. Pixie smoke? You might ask. Well, when you buy something like an Arduino, which is basically a little computer, there’ll be lots of little black boxes on them with circuitry that performs a specific function, allowing the little computer to work. These little boxes can contain some fairly complex circuits that do very simple things, however, doing simple things a few million times every second can trick us slow-thinking humans into thinking they’re doing very complex things. People that understand these tiny black boxes in an intimate way are very rare but people that use them every day certainly are not. Usually, when these boxes stop working it’s as a result of something getting too hot inside and melting which also melts the black plastic enclosure and gives off some very nasty smoke. So for all those people that use and break these boxes often but have no need or desire to learn how they work inside, the traditional pseudo-explanation is that they’re all simply enclosures for different kinds of magic pixie smoke which does a specific job. If that pixie smoke escapes, the little black box stops working. Some engineers and hobbyists are cool, though.

One such little black box, the slick looking patches are where the pixie smoke escaped from. Look forward to reading about this failure in a future post.


Having put this particular large wooden box together myself I was frustratingly aware of the fact that this smoke signal for failure I was accidentally sending out was not in fact a cloud with mystical properties, rather, it was the result of insulating a heater capable of reaching 300°C with wood. Wood, as luck would have it, generally catches fire at around 300°C. The more you know.

The heater was in the copper spring type part, which was in the wooden block. More wood was used to insulate the bottom of the spiralled copper but it escaped unharmed. Clearly the wooden block pictured though has indeed been very much on fire.


So, frighteningly aware of the fact that this smoke meant I had started a fire, I turned the heater off. Smart move. Smoke and burning persisted though. As you probably know, fire needs two things to burn – fuel and air (oxygen). It was only the inside of the wooden block which was in contact with the heater, so only that part was on fire at this early stage and the snugness of the fit meant that air flow to the embryonic blaze was pretty limited – even though it was surrounded by wooden fuel on all sides; ironically, it was this abundance of fuel that was preventing it from burning by limiting its access to oxygen. Had I Let It Be, it would have suffocated fairly quickly and died off. I didn’t, so it didn’t. Instead I decided to give it CPR, but, in my defence, you blow on a candle to put it out and I’m not sure I’ve ever had to fight a fire in any other situation. So, when I saw this small flame with ambitions of cooking all the food in my freezer (and the freezer too), I instinctively blew on it. It, in turn, instinctively flared up in exultation as it could finally take the breath it had been gasping for since its inception. I decided not to do that again. My second smart move of the day. Instead I watched the fire slowly suffocate and armed myself with a wet sock to finish the job if required, like some kind of sadist. The smoke brought a tear to my eye, but the death of the fire brought a smile to my face – nervous and disconcerted as it was.


Sometimes people that know CPR, that know mouth to mouth, just like me, should keep to themselves.


I did another very quick and cautious test with no wood around the heater and saw it glow red hot almost immediately, which I didn’t like. The problem is that I thought the heat could just go immediately from heater to copper tubing to cup to water. In reality there’s a lot of lagging at every stage and what I need, apparently, is something with enough “thermal mass” to capture and hold the heat from the heater until the cup is ready to accept it. Basically, I need a bigger block of metal as a hot plate and more of it should probably be in contact with the heater too.


I have spent a few days now trying to get copper blocks or aluminium blocks with the exact right dimensions, but they just don’t seem to be available. After hours of sickening myself looking for the perfect block to use I had a moment of weakness, I saw a block of steel that was roughly right and bought it immediately. Immediately after that I realised it was the wrong size entirely and now, even more sickened, I’ve bought a slightly larger one that is actually about right. The problem, though, is that it’s a large block of steel and I haven’t done nearly the amount of research I should have into whether it will be up to the challenge in order to justify buying it. But that’s a problem for when it arrives.


The reason such blocks of steel exist is actually for use as tiny anvils which jewellers use as a work surface as they hammer bits into shape. Some, like what I’ve bought, are just blocks but others are stylised as actual anvils and would make a pretty cool paperweight. But honestly, what even is a paperweight? If you want a desk toy because it looks cool buy a desk toy because it looks cool, not everything has to have a purpose outside of looking cool.

Case and point: Spoilers on your road car. They might never have to actually affect air flow or fulfil any other purpose but they don’t have to. Because they’re just so good at DEFINITELY looking cool, and hey, making you look cool while they’re at it. What an incredibly cool looking thing.
1

The Robin Hood of Robbing Heat

Copper Wire

TL;DR: All parts have arrived, immersing the heater into a cup of water brought the water to temperature in about 20 minutes. A hot plate has been fashioned for test 2.

I ensured all the parts for the clock were due to arrive on the same day, that way I avoid any risk of losing motivation. Right now, they’re scattered unceremoniously on my unmade bed but everything seems to be in order. First priority is to transfer everything to a well partitioned box so it’s all easy to find. Now that’s done, what to test first? There’s only one answer here – the heater. All my maths indicated a 50W heater could take as little as 20 minutes to boil a cup of water. Now, here’s the issue – pick any noun in that last sentence, got one? Prefix it with imperfect. My maths is just lazy and the cheap cartridge heater probably isn’t actually 50W output. The cup isn’t a fantastic insulator so it will let heat escape and the water within the cup won’t always start at 23°C. I think that’s call for some real-world tests.
The first test is going to be the heater connected to the power supply (through a switch for control) and the hot end dropped into a cup of water, immersion heater style. This is just to prove the heater can indeed heat water in the real world. Enjoy the following contrived analogy for the practical inaccuracies suffered at the expense of operating in the real world:

Cast in order of appearance:

Robin Hood – The cup
The Rich – The water within the cup
The Poor – The air around the cup
Maid Marian – Entropy


The cup will act like the Robin Hood of robbing heat. The cup itself has no desire for heat, in fact, it would quite gladly go through life at room temperature with its mind on other things. The water within the cup, conversely, has made its life’s goal to accrue as much heat as possible. Looking around in any direction all the water can see is the ever-ruminant cup. The water can only assume then that the rest of the world does not value heat so dearly, those without heat can get by with the same lofty attitude this cup has adopted. So, the water retains vast amounts of heat for itself, obscene amounts to you and I. Obscene amounts as the air around the cup would view it too. This surrounding air laments over what it could do with just one morsel of heat, perhaps it could rise and escape its cold and desolate dwelling.

A photo from Nottingham Forest Recreation Ground which I mistook for an immensely disappointing Sherwood Forest. Friends were quick to inform me that there is more than one forest in Nottinghamshire and while Sherwood Forest is not disappointing, my intelligence is.

The cup can see the vast amounts of heat possessed by the water, the cup can also see the air crying out for any touch of heat, finally, the cup can see the disparity between the two sides – so the cup can see injustice? Possibly. But the Robin Hood of this story is so blinded by his own apathy towards heat that he does nothing to even the playing field. He is unsure how to proceed – he could steal from the rich (heat rich) and bestow upon the poor, or, he could teach the poor how to live like him and be content in their cold slums. He spends his time arrested by and enamoured with this vision of teaching strength despite poverty and how he could become the being that all those beneath him strive to emulate. However, he neglects to notice that for people to have to strive to be like him, they must not be like him, and thus, perhaps they do not have the capacity to ever be. Like him, that is. He fantasises nonetheless, all the while, the poor air is unable to summon the energy to let its mind wander to such frivolity; thinking about anything other than where it can source heat is a luxury. Every thought that enters the air’s mind is just a veiled cry for warmth:

“What is that?” read “Is that a heat source?”

“How are you?” read “Have you found heat?”

“What time is it?” read “How long has it been without heat? Surely some will appear soon!”

The suffering continues. The air cries for a saviour. Enter, Maid Marian, our character to represent entropy.


Entropy is sickened at the thought of the existence of such disparity between the haves and the have-nots, but entropy is far above exacting equity herself. If she were to be preoccupied with actually resolving every injustice there was, who would call attention to the infinite injustices that arise every second? No, Maid Marian must call others to action. Maid Marian, so alluring to the lost causes that with the bat of an eyelash she can summon the breeze that knocks our Robin Hood off his well-worn perch atop the fence. Dreams of achieving idol status to the air are cast aside and replaced with fantasies of being in the company of something so perfect as entropy, even in the capacity of a servant. Immediately the cup sets to work, robbing heat from the water’s relative excess and disseminating to the air on the other side, assured by his Maid Marian that what he’s doing is justified. Truthfully, whether or not anything is justified is irrelevant to him now, the objectivity and altruism that he had mused upon while procrastinating on the fence has been replaced by one question: “What would Maid Marian do?”. If he weren’t so blinded by his infatuation, he might realise that what he’s actually asking is “What would Maid Marian have me do?”. If he weren’t so blinded by his infatuation and his ego, he might ask “What would Maid Marian have someone do?”.
This tragedy unfolding makes it very difficult to say exactly how long it will take for the water to heat given that so much of its heat is redistributed to the surrounding air by our wily protagonist. The only way to really find out how long it’s going to take is to experiment, or at least that’s the only way for someone with my limited understanding of thermofluids to find out.

Unexpectedly, I got the expected results. Immersing the heater in the water produced water just hot enough for tea in around 20 minutes. Lovely stuff.

That first test, test number 1, didn’t really call for me to leave my room at all, now though we get a bit more involved. The next test requires wrestling copper tubing into something resembling a hot plate, at least functionally, and setting up some sort of a test rig. And so; to the garage.  
The garage is fairly large and well stocked with tools, I’ll set up camp on the top of the chest freezer, moving to the workmate when I need to clamp anything. The main inconvenience is the lack of working lights. I could certainly tackle this issue before beginning work but even when the lights did work, they were more “less-darks” than lights. The exposed rafters meant that rather than being reflected by a ceiling, most of their light loses its way amongst the clutter above; expired sports gear, a paddling pool put away “until next summer” and old tins of paint used to bring colour to a house that now only exists in childhood memories. At this stage these artefacts have all but accepted their state of disuse, becoming jaded with the prospect of being brought down and given new purpose, but if the lights come on they still sluggishly attempt to catch it in a flattering way so as to remind me of the good times. All of these knick-knacks of nostalgia trying to catch the light ensures that very little actually manages to light the room. So rather than fix the lights I’ll work by head-torch, that’s much more mad-scientisty anyway, I like that.

a whitegoods workspace


Forming the copper tubing into a spiralled plate isn’t as easy as I anticipated. The first thing I noticed is that the more I manipulate it with the pliers, the more scuffed and crooked the tubing becomes, I’d like to keep all that to a minimum since the relatively expensive copper was mainly chosen for aesthetics in the first place. Using my hands rather than pliers is time-consuming and not exactly comfortable but eventually I’ve ended up with something like the picture shows where the heater fits nicely into the middle protrusion.

Copper Wire
The copper “hot plate”. Centre coil to hold the heater. Large spiral flattens under the weight of a cup of water – permanent flattening and improved shape is an issue for another day.

Ideally, that smaller coil that cradles the cartridge heater will wick the heat away very quickly and allow it to be transferred across the spiralled tubing which can in turn heat the bottom of a metal cup, which will then heat the water. There’s a pretty much constant draught in the garage so to avoid the air stealing heat away before it gets to the water I’ve made a sort of wooden enclosure for the whole thing – anything getting hot can either give its heat to the wood or to the metal cup. Hopefully, the metal cup is the more accepting of the two.

Test number 2 is now underway. Test number 2 has failed. Abort test number 2. Assess damage from test number 2.

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Bravado as a Writer in the Dark

TL;DR: Why writing a blog was always going to happen: I met a whole lot of people that had a whole lot of things they cared about – I wanted that. One day I felt compelled to write and it’s always been something I enjoy.
Why now: This project makes for a good documentary and I’m scared of YouTube comments; I met another whole lot of people who normalised sharing creative content; I want to practice to write a book that I’ve only recently had inspiration for.

Following the fairly technical “Utah! Get me two!” post and given I’m pretty sure most people reading are more into reading blogs as a hobby than creating electronics projects, this is a good time to post about my blogging motivations.
This is a long one and attention holding photos as spacers were tough to come by, maybe take a few goes at it. The song titles are separators.

I could go into detail about how I always enjoyed writing, appreciated well-written literature and have been told I “have a book in me” but I suspect that these narratives are intrinsic to most blog-readers’ lives too and I doubt my ability to write about them in a way that gets a reader excited about relating to it. More likely is it reading as a boring and self-absorbed account of my perceived uniqueness. So I won’t do that. Instead I’ll skip ahead to 2018 and the summer I grew up:

Reminiscing about childhoods makes great fodder for easy-going conversations because most of us have broadly similar experiences; grown ups are much more unique and thus adulthood makes for more interesting and stimulating stories. And I didn’t start to grow up until the summer of 2019, at 20 years old. I moved to Wales for my first full-time job. All the responsibilities of adulthood set in: If I don’t cook I don’t eat? I have to develop a sixth “drying weather” sense to know when to hang my washing out? Wait, tax? – Realising the answer to all that and more is YES certainly helped me become a functioning adult and equipped me with the ability to go through the motions as a human being, but I (we) need more than that. I (we) need to grow.

1 – Everyone Blooms

My granda always had sweet pea growing in his garden, as you walked from the back door to the patio there was one moment along the path where the sweet perfume commanded you to look left to the wall of colour in your peripheral vision. You never looked right. The signature of the muted but deeply complex marbled lilac petals in the corner of your eye is engrained in their fragrance so that you immediately know where to turn. Like how you know to look at the green shop front when you smell the herby, savoury delight that is SubwayTM bread – not a sponsorTM. The way we planted the sweet pea every year would ensure the type of foliage upon the trellising that looks fuller than is naturally possible, enwreathing the evanescent wooden lattice behind it. The illusion created was such that when you stood facing the wall of green, lilac, white and pink, it occupied your entire field of vision, stretching beyond your peripherals and so thick it was impermeable to light from behind. But more than just being optically overwhelming, the natural perfume filled your nostrils and sent a second sense into a trance. A perfume that is so sweet and engrossing, yet gentle and light that only nature could conjure it – only the same force that forms our perception of the world could create something so perfectly engaging to our senses. My favourite sensation it produced, though, is the illusion of the ground somehow occupying two axes at once. Generally, we know if we start digging in one spot all we’ll ever hit is dirt; infinitely, incessantly, inexorably present dirt.

*Apologies, geographers and archaeologists, I’m about to be real offensive*.

It’s that innate knowledge that no matter how much effort anyone puts in all that they’ll find is dirt which gives the sense of grounding we need – something secure to depend on – the ground is beneath us, no matter what anyone does. Now, I can’t begin to articulate why the wall of sweat pea appeared as a second, vertically oriented ground but I do know that staring it down I always felt that if I tried to put my hand through it, all I would ever be able to feel was the supple petals and ridged stems of the flowers as they continued further than I could ever reach. There was no ‘beyond’ the sweet pea, just like there is no meaningful ‘beyond’ the ground – yea, Australia’s down there somewhere but I’ll never be able to reach it through the ground. Giving myself over to believing that I was facing the ground I could feel a weightlessness come over me, the only force I was aware of was my own breath pulling in the perfumed air, which was just as weightless as me. All these sensations rose up even having helped measure and erect the trellising myself and knowing that the plants were only planted one layer deep.

The trellising never went the full way to the ground – damp soil and bugs would quickly rot the thin wood from the bottom up. So each sweet pea plant needed a single support pole to climb up in its infancy and ensure it grew to reach the trellising. When it did, it could then go off and climb along any combination of slats it chose, sometimes using other plants to support itself in an effort to reach a specific area where it felt it belonged.

Are you ahead of me on this one? Probably. I’ll say it anyway; humans are like sweet pea. Those early stages we are well confined by whatever path of best support is in front of us – usually the path is being “destined to become a lawyer/engineer/business person/vet/entertainer” and following a route through education that ends with that career. There’s enough going on as a child to have your time fully occupied even when you’re just going through the motions – not giving too much thought to the fact that life might not just be a linear journey up that initial support structure. You don’t begin to truly know yourself until you graduate to the trellising. Sure, you can keep following a straight path up and probably grow to be the tallest plant; but the others, having taken more convoluted paths with twists and turns and becoming intertwined with their fellow plants will find themselves in the sun more often and bearing more flowers.

2 – Lean on me


When I moved to Wales (in summer 2018) I had most certainly graduated to the trellising, but I was also just trying to be the tallest plant. Or in my case the best candidate for an engineering job. The reason I moved to Wales was for a placement as part of a scholarship I had won which had very promising career opportunities; I guess I was succeeding as a pretty tall string of green vines. Pardon the ego.

Every year there’s a summer seminar held for the 150-200 scholarship winners, spread across different universities and sponsoring companies. I don’t think I ever bragged a lot about my success, but internally at least I firmly believed that winning an IET scholarship was the pinnacle of anyone’s university career – I’m sure that has spilled over into ill-timed boasts every now and then, and probably still does. Having dinner and breakfast with the other students made me realise how little of life I had experienced though. Given what we all had in common I thought it was going to be a great ego-inflation event where we could congratulate ourselves by congratulating each other. Shamefully, I think I actually wanted that. But no, while I feasted on fancily arranged, cubed vegetables and pretended to enjoy red wine, my ego starved.

“What have you enjoyed most about university so far?”

I thought was a good opener to invite the response:

“Getting a scholarship of course!”

The whole table would pause and then, in unison:

“Me too!!”
*uproarious laughter with people in the room, implying laughter at people not in the room*

And we’d mutter our boasts and self-assurances over the scraping and clanging of me manipulating my butter knife and dessert fork, each of which in the improper hand, to investigate my starter of miscellaneous fanciness.
The responses I actually got:

“Well I spent a semester studying at a partner university in *insert obscure, impressive sounding place* it was mind-expanding,”
“Oh I started a business based off a project I worked on and we’re doing well.”
“I got engaged last month and I love him so much.”
“I’m president of this society and that club and I’ve made them so much better.”

I’ve reassessed my approach to university in a major way twice; these replies inspired the first instance. I realised I had always looked at the clubs and societies as either frivolous distractions for people who came to uni for the craic or a means to get a leadership role for the CV. But the way these people explained what they had enjoyed about university made me realise I had got it completely wrong. I want to stress these people were genuinely passionate about all these things; reading my vaguely worded sample responses back it sounds like I’m trying to make them sound facetious – not the case.

This is the point where I started to first reach out, away from my straight vertical slat and see if the other plants around me could support my weight. Not only where they up to the task but now they would point me in the direction of slats that might interest me and even suggest twisting together to support each other as we grew towards it. This is the time I began to really pay attention to myself and other people, listening with the hope of being inspired to action and then acting even with a very probable risk of failure. I was sickened at the thought of continuing to just go through the motions until I got to the end goal of being an engineer and only then taking the other aspects of my life as seriously as my career. It was a real awakening. One inspiration that came from just listening to myself is wanting to write. I know that was a convoluted story with a very concise conclusion but it was truly just like that for me. One day I wanted to be a writer but didn’t know it and the next day I knew it. It was just a matter of being asked – like when someone asks if you’d like a biscuit. So I started looking for inspiration for something to write about, initially I assumed my first written material would be a novel but evidently not.

3 – Up on Melancholy Hill

The walk around the ‘foot’ of Castle Hill – The closest I have to a photo from the top is the photo of the old lifeboat house you see on the home page


In Tenby, Pembrokeshire, there’s a hill with magnificent views of the water. I brought a lot of books with me to occupy myself in Wales and ordinarily Castle Hill would be the perfect place to read them but I never got through a single novel there. That entire summer any time I was alone on that hill I was obsessed with this new outlook I had on life and trying to dream up new things I wanted to apply myself to. One evening in particular the water was just one, very low, undulating wave reflecting what was a pristine sky. A small boat was bobbing up and down quite far out and I got thinking about the tide and how much I loved the Pembrokeshire coast. I imagined myself down there in the water, feeling it gently rise and fall from just below to just above my knees and back again while I looked around at the colourfully aged cliff faces. That inspired the first thing I ever seriously wrote. A very short ‘poem’ (or just verse? I’m not sure on the semantics) quickly jotted in my notes app, just for me. I thought (and still think frankly) it was pretty good. But I wasn’t (and still am not) convinced. Regardless, when it came time to leave Wales I wanted to leave something behind; the people I lived with there deserved to know how much I loved their home and that without them it wouldn’t be their home and so I wouldn’t have loved it so much. So I wrote the poem inside a farewell card, bought some presents and one evening left it all on the kitchen table. I should have called them in then and shared the moment with them, but the thought of being able to see their face as they read it, contorting in that “I’m not sure what this is but I know I don’t like it” fashion which is always followed by a facetious smile and an “oh, that’s nice” was too much to bear. So I went to my room and came down later when I knew they had been in the kitchen some time and had a chance to formulate a polite response to my nonsense. I think they liked it, though. It went:

A Smile
The same tide that has formed the natural beauty all around me
Now moves through me
And across my face
The most natural of beauties, now grows

So that’s the very long story of me learning that I want to write, resolving that I can write and attempting to write. Since then I haven’t written much else but inspirations have popped up here and there and a blog was always going to happen. More on that in the next part. This is a pretty good time to stop reading and come back another day if you haven’t already.

4 – Big Bird

Why now? Three reasons. First up is undertaking the Arduino project. I’ve always said if I was born 5 years earlier I think I could have had a stab at being one of the initial engineering/curiosity channels on YouTube (VSauce, Veritasium, Practical Engineering). In reality I could start now and if I was good enough I’d be successful but it’s easier to just say I missed the window. Even with this belief that I’d have to be exceptionally good to gain any sort of significant viewership, my first thought as parts started to arrive for this alarm clock project was that it would make for a good video series on YouTube. I don’t want to spoil the illusion but at this stage the alarm clock is pretty much built, the blog is lagging well behind and even now at the end of the build I believe the whole process would have played out well on camera. I’ve used so many engineering principals that it would make for a great long form talk covering a bit of everything, plus there’s the sensationalism of tests ending in fires, laptop crashes and board meltdowns. I’d certainly want to watch it if the almighty YouTube algorithm decided that I wanted to watch it.

However, I’m terrified of that prospect; YouTube has comments and an unpredictable audience of critics. I love YouTube, it’s easily my main source of video entertainment and has been for a while but the comments are ruthless and I don’t have the stomach for it. I always thought the toxicity was overplayed by creators but then I realised I was just reading the comments YouTube and a democratic and mainly well-adjusted viewership allowed to float to the top. Go on any video and sort comments by newest instead of most relevant – you’ll be horrified. Factor in the fact that the videos would be badly edited and include my stream of thought commentary as I go about pretty much every task in the wrong way and it becomes easy to see where my anxiety about the whole ordeal comes from. There’s also the fact that YouTube comments are more personal, criticism is always voiced in a way that implies the creator is inherently flawed and incapable of change. Writing a blog, I can make it much more removed from myself. I absolutely invite criticism here as I’m trying to develop my writing skills, if nothing else for future posts. It’s much easier to see criticism here as a constructive judgement on one aspect of myself, an aspect that I’m not only capable of changing but am actively seeking ways to change because I know it’s flawed. That’s about the most straight-forward reason here. I started the blog for this project because I was too scared to start a YouTube channel.

As an aside – I do feel as though a blog would have happened later, more than likely with music providing the narrative somehow or serving as a more professional insight into my character. It was always the plan to make a blog at some stage. However, I always wanted to use it as a reason to learn how to develop my own website from scratch. I probably will do that at some stage, possibly making a more professional, career oriented site, but I saw the opportunity with writing about this Arduino project and took the quick and easy option of WordPress. For now.

5 – Brooklyn Bridge to Chorus

“Why now?” Reason two: Since that moment at the seminar where I found inspiration in other students and up until very recently I’ve been pretty insufferable in my own opinion. That internal shift of beginning to look for and be more open to inspiration lead to an external shift of often appearing disinterested, aloof and bordering on stand-offish at times; counter-intuitive, I thought. Basically, I managed my desire to want to learn and attempt new, interesting things in a very immature way. I started to get very hung up on the pointlessness of small talk and expected people to just immediately jump in with an inspirational story to tell me. When I felt a conversation was of little value I often shifted to put less effort into it and let my mind wander to whatever the next big thing in my life was because I just had so many important things going on (/s). Even when I met new people who I knew had a story to tell and who I absolutely wanted to have as part of my life I was a horrible conversationalist. Selfishness-induced, adult onset social incompetence. I lead with presumptions and had no issue appearing as if my mind was somewhere else; supposedly somewhere much grander. I still can be a bit self-absorbed, and no doubt I had been at times before Last Last Fall, but a lot of reading and reflection has at least allowed me to notice when I do wrong.

Thankfully a lot of people in my life are bright enough that they can swing even the most lack-lustre conversation into a deep exploration of some amazing facet to their life. Included in those people are a lot of people I met during that year after coming back from Wales as I incorporated myself into a lot of new groups in line with my no longer latent passions. Through meeting people who publish creative things, it normalises writing a blog, just like meeting people who enjoy cooking normalises spending a weekend experimenting in the kitchen. I don’t think I’ve ever consciously shrunk parts of myself in an effort to avoid being different or ‘weird’ but in retrospect I can conclude that a lot of what I have done is very ‘normal’, as defined by the people I have always had surrounding me. I would never write a blog because none of my friends write one. What’s the point in doing something if it won’t help me find my Bravado and get the applause, the approval, the things that make me go oh. I don’t think having met more people that share their creative work has necessarily convinced me that I now have an audience who will like my writing but it has certainly normalised the act of writing a blog and sharing it with friends.

So I’m very thankful that I’ve met such a variety of people who have persisted as part of my life despite me taking myself very seriously for the last while and being very analytical about everything they say, trying to involve myself somehow.

I’ve picked up a lot of habits recently, reading a lot on mindfulness and communication skills, being conscious of the present, reflecting at the end of the day, even yoga and, most importantly, talking a lot more. I still catch myself sometimes not engaging in a conversation the way I should but at least now I’m catching myself on it. Now is the first time I think in my life that I’ve been so acutely conscious of my own unique perception of the world and been happy with it. Now is a good time for me to start creating content that goes on the internet. Forever.

6 – These Words Are Everything

The last reason for the blog being written now is that I very much want to write a book. As I said, I’ve always thought a novel was brewing but inspiration for something so substantial was lacking. I have creative thoughts where I’ll imagine a scene, or a way to describe something in great detail, or short aspects of a story/character which will pop up quite often. However, an overarching theme capable of forming a storyline has proven elusive until very recently. I came up with a concept that I think I would love to read a novel about and I know all the little tidbits I have noted over the last 2 years can add flair to a story that I would appreciate; so I sat down to write.
Apparently it doesn’t work that way.

This is why I don’t think a potential audience is a major factor in writing this blog. The biggest reason I have started it is because I want to learn how to write for an audience. Not because I think I already know how. I want to have shorter pages that I put through multiple revisions on the off-chance that someone else reads them, I want to practice re-reading and re-writing until I actually enjoy what I’ve written myself and I want all the records stored somewhere so that I can reflect on them forever. I really, really want to write a good book, even if I’m the only one that ever reads it, which I know is very probable.

The concept I want to write about is one of my absolute favourite things to appear in other art forms and I want to do it justice. If I finish the book and when I re-read it realise that the whole thing is just poorly approached and poorly executed, I’m not sure how I would manage that realisation. Quite possibly I’d burn the manuscript and never try to apply myself to anything new ever again. Maybe move to Nepal and live as a mountain goat. So while all the above reasoning is absolutely true and relevant, most of it would have been true and relevant to any blog I started. This blog is the way it is, with liberties taken to use figurative language excessively and go off on tangents, because some day I’d like to read a book I’ve written and be proud of it. This is practise.

There you have it, the main reasons I can think of for my writing of this blog. Next up I’ll start into actually commentating on the build process of the clock. This post was pinned for a later date but I think I needed to make up for the excessive electricity chat in the last post, at least momentarily.

Note to self: Learn when to use “whom”, it almost certainly applies to this post.

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“Utah! Get me two!”

TL;DR: Rounding out the parts list; stripboard to solder everything onto, switches for safety features and controlling the lamp, a capacitive sensor to wake the clock screen and MOSFETs to control the currents that the Arduino can’t directly. Electricity is dangerous.

This isn’t the most universally entertaining post, it’s quite technical. The next post will be more creative talking about the blog itself and going momentarily off the narrative of building the clock. For this post there’s levity injected where possible but that’s not so regular, as you can assume by this disclaimer: I don’t recommend trying this project. This is not an instruction manual or reference material for electrical work, I am a very inexperienced engineer writing (believe it or not) with the intention of being entertaining, at least to myself. Assume everything I write – especially about health and safety – to be completely subjective and even more-so completely incomplete. For example, I conclude 12V is probably harmless; that means 12V DC, through my skin, while dry, at room temperature and for less than a few seconds. All of that is far too mundane to include in a blog that is already fighting against by abilities as a writer (or lack thereof) to be entertaining. Stay alive.
For the uninitiated, the footnote* (foot-essay) might be worth reading first – only the first bit about why wires might get hot though.

The basic parts list is now done; cartridge heater, LEDs, copper wire, clock, LCD. However, there’s a few more bits to add, mostly as a result of working with the fairly substantial 60W power supply. Given the supply provides 12V, my highly resistive skin should provide me with all the protection I need to avoid electricity induced burns or muscle contractions. While my skin is highly resistive, all sorts of things effect that, wet skin that has had a potential difference held across it for a long time (e.g. if I’ve just come back from the bathroom and am absent-mindedly holding wires while I try to regain my bearings) can start to accept a lot more current than it ought to. Essentially, electricity preys on fear; every bead of sweat that coats your hand makes it easier for the energy in one wire to make its way to the other by forming a path of destruction through your skin, nerves and muscles. Every second you hesitate, it breaks down your skins defences, bending your body to its will until your natural defences are overcome. Electricity pursues its mission to go from high potential to low potential with the type of tenacity and ruthlessness that extreme capitalist culture encourages people with a lack of empathy to pursue the opposite path – from low to high potential. As far as electricity is concerned the only difference between a path and a roadblock is time.

Lightning isn’t so much just a matter of time as the potential difference between the clouds and ground is actually getting higher. However, if there was a somehow lightning bolt shaped path of especially humid air, it’s definitely more likely to see a strike, similar to wet hands – more water means lower resistance (in these cases). Pretty similar concept to when things short circuit if you spill water on them too. Photo by luiisrtz on Pexels.com


Still, substantial current through me is unlikely, but if I drop a screwdriver which lands on some wires, current might flow through it and it can quite quickly get hot enough to burn me as I try to pick it up, then I’ll recoil as if in fear of this possessed screwdriver pursuing a further attack. It’s that recoiling that can lead to me hitting my head on the table or slamming my hand on a drill bit or something hot. I know that sounds like the conjecture of an overprotective mother but you learn very quickly working with electricity that these fears are well-founded.
The tidiest workshops you’ll see are those concerned with electrical equipment, the electricity supply in such workshops (not in your house or garage) is fairly safe with so much in the way of safety switches and fuses but it will still shock you. Its your knee jerk reaction that’s dangerous – a quickly retracted arm is a prime target for the exposed blade left lying around after stripping wires. Or perhaps a flailing leg is the mechanism by which the acid, imprisoned in a testing jar against its will for too long, makes good its escape. These risks are very real and make one appreciate a tidy workspace. It is wise, then, for me to keep track of where things are and where they should be, but also to buy a few switches, allowing me to turn the supply off without unplugging it every time and, more importantly, without being close to the plug. I’ll just need to make sure I know very well which side of the switch I’m working on at all times.
The switches will also find use in the end product, one to allow me to turn the light on and off like a normal lamp. Another as a sort of disconnector for the heating system as the heater says it’s comfortable operating at 350 degrees Celsius. That’s fine for the heater but everything around it, including me, would be very uncomfortable if it got anywhere near that. So I’ll need a kill switch to keep it in line in case the innate pyromaniacal tendencies ever take over. My main concern is the brains of the operation, the Arduino, coercing the heater into some sort of suicide pact while I’m not around, or teasing it, saying “I bet you can’t really get that hot”. So to prevent this I’ll put the heater into isolation from the rest of the circuit by flicking a switch as I pick up my morning cuppa and reconnect it when I set a new cup on at night. I agree; isolating the innocent, naïve party is the wrong approach entirely, the heater would never turn itself on if left unprovoked by the Arduino – the bad influence should be the one that suffers social isolation all day. Unfortunately though, reprimanding the Arduino will only lead to the rest of the students – I mean components – acting out. It’s the coward’s way out for sure but thankfully the heater doesn’t have the mental capacity to be instilled with trauma from this dreadful mistreatment. A mistreatment which only serves to accommodate the obviously emotionally incompetent and lazy teachers – I mean technically incompetent and lazy me – who can’t be bothered to work out an alternative. This of course wouldn’t be a bothersome thing to work out for a more competent engineer. So the real root of the problem clearly lies in the training processes completed by the people charged with the care of these children – I mean person charged with making this clock.
If I was to detail the problem more literally – the Arduino might turn the heater on due to a bug in my code or an unplanned clock reset. If there’s no cup to heat, there’s no telling where that enormous amount of heat energy will get redirected to – my fingers, though, trembling with trepidation almost to the point of forgetting they’ve got a job to do in typing right now, seem to think that they’re a prime target for getting cooked.

I’ll use a stripboard to link all components together – not much to say about that, it’s just a lot of strips of copper on a board that I can solder things to, making a circuit. They come with good current ratings so I can avoid anything getting hot.

Switches are fine for most things but to wake the LCD screen and request it to display the time, I think a touch sensitive button would be pretty sleek. I have an old phone which pretty much every part of has perished and figured the onboard fingerprint sensor could do the job, so I set about taking the phone apart, brutally ripping off its already busted screen and leaving my bedroom floor looking like the 33rd floor of Nakatomi Plaza in the process. Heartbreakingly, the sensor had special connections that I couldn’t make use of. Which I most certainly could have just found out using Google.
Thankfully touch sensors are fairly easy to make from pretty much any sheet of metal and a resistor. One of the heat sinks in the phone is a perfectly sized sheet of copper to make a button out of, so the John McClane cosplay wasn’t completely in vain.

A touch sensor (the blue wire and everything to the right of it). Quickly prototyped on a breadboard using a steel soldering iron rest as the “button”. The bigger the metal sheet used, the more sensitive the button is – in this case I could just hover my hand near it and still be sensed.

Lastly but probably most importantly, we need to return to that whole Arduino being a bit of a manipulative bully analogy from earlier to understand why I need MOSFETs – that’s an acronym, I’m not just super excited to talk about these special transistors, I am a little excited, though. During uni I’ve looked into pretty much every analogy to try and understand a transistor’s inner workings; the interesting ones don’t explain it well and the ones that explain it well aren’t interesting, so I’ll spare you any attempt at describing it. The outer workings are pretty intuitive though – basically, the heater draws just over 4 Amps while (hopefully) boiling water, but the Arduino is unwilling to give it any more than about a tenth of that for fear of morphing into a heater itself and everything getting a bit melty (noticing a theme?*). To get around this, the Arduino can delegate the supply of current to the heater to a MOSFET, which is more than capable of commanding 4 Amps, but not without explicit commands to do so. Whereas before the Arduino would have had to push with everything it had and more to get the heater to even think about doing its job, it can now simply wave its hand to the newly appointed and very obliging enforcer which will wrangle the heater into compliance. MOSFETs, and all transistors, are basically switches that machines can control. So the heater will have its own direct line to every bit of power that the Arduino has access to but the MOSFET controls whether that line is in use or not, and the Arduino decides what the MOSFET decides, and I decide what the Arduino decides, and . . .
I also think I’ll use a MOSFET to control the LED, it’s not really necessary here – I could wire it differently but incorporating the switch that allows the use of the LED as a regular lamp outside of sunrise hours gets slightly more involved and MOSFETs come in packs of 10 anyway. Pretty much everything I’ve mentioned on this shopping list has had to be bought in a pack of at least two which should be great for experimenting.
Other than that, a few wires, a roll of tape and some solder will be needed but as best as I can make out the shopping list is complete for now!
I’m not sure if I’ll actually write about this but I’ll also buy a few smaller LEDs and a breadboard which can be great for verifying the code works without getting a 12V supply and 50W heater involved.

A simple circuit using a MOSFET – the silver thing with a hole in it. All this circuit did was turn the bulb on and off. The silver holed part is actually just a heat sink, the magic happens in the black casing,. The fact that these come with a means to get rid of heat quickly should confirm that these little things can wield some serious power.


* A note on electricity and heat: People often think live wires are thermally hot – they shouldn’t be. The wire getting hot means it is giving off power as heat – where is it getting that power? It’s stealing from the power you have tasked it with carrying to your phone’s battery.
If a wire has a limited number of electrons, (the particles tasked with carrying electrical current) attempting to transfer large currents means the electrons are overworked and start making mistakes, bumping into each other and generally getting all hot and bothered. The more this happens the more they hit each other and the more temper(ature)s flare. So it’s very important to ensure your wire has enough electrons to carry the current you’re trying to send through it, otherwise they’ll waste so much of it bumping into one another that the majority of your power has been given off as heat before it gets the chance to reach whatever you were trying to power. Thankfully the solution is simple, just employ more electrons – use a thicker wire, split the current between two wires or use a better conductor (with more free electrons per unit volume). There’s other ways too.
The wires in the Arduino can carry 2 Amps without getting hot, above this they heat up and start melting the plastic board they’re embedded in.

I suspect no-one will be reading at this point – I’m about to tackle why touching live wires burns, even if the wire itself isn’t (thermally) hot – “hot” can also mean live when dealing with electricity. Honestly it’s only worth reading if you’re really interested, I’m mainly writing to improve my own understanding of it, I’ll still try to make it readable but it will be devoid of figurative language. Again – this is incomplete and quite possibly inaccurate!!
If you put current through something resistive it will dissipate heat power to the tune of I2R; the current through it squared, multiplied by its resistance. Clearly if you’re using a high current then you need a very low resistance to avoid too much heat being dissipated. Also, voltage is equal to the current multiplied by resistance (V=IR for the acquainted). Voltage is the thing to watch out for primarily – also called potential difference as it represents the electrical potential between two points. A 12V DC supply like I’m using will have 12V of electrical potential between the red and black wires, if I were to grab both with one hand and my skin had resistance of 100,000 ohms, the current would be 0.00012 Amps through my skin. So referring back to the previous formula, 0.000122 x 100,000 = 0.00144 Watts of heat is dissipated by my hand – that’s just over the power my Wi-Fi router antenna emits – and I can hold that all day without getting warm. The FCC makes sure of that.
At higher voltages the heat dissipated by my hand will increase, the wire isn’t getting hot, I am. The maths for working out where real burning would occur is maybe a little beyond me and honestly pretty pointless since there is always the danger of something other than my hand coming between both wires and getting hotter than my hand would, coupled with the danger of me touching that something. Also, at a certain point, skin starts to get broken down because of electrical potential across it, causing its resistance to drop and allowing more current to flow – trying to factor this in is pretty much pointless as there are too many variables that will change every time you work – “have I showered yet today?” and “what did I have for lunch?”
Also important is that long before burning actually occurs, other dangers will get to me, our brain communicates using minute electrical signals and so our pain receptors are fantastic at detecting electrical current, so while I may not be burning, I will be feeling tremendous amounts of pain. Muscles also begin to be overwhelmed by electrical signals and start convulsing, particularly troublesome around the lungs and heart. Although, humans being the fantastic race we are have developed life-saving defibrillators based on this principal to kickstart the heart with a big current induced contraction.
Also also important is that mains supply and a huge amount of what you are likely to encounter is AC, not DC, which is something I shan’t go into except to say that AC doesn’t find your skin’s resistance to be so much of an issue.
Electricity is very dangerous. Taking advice from strangers on the internet is very dangerous. Inferring advice from an entertainment-driven blog is very dangerous. Inferring electricity-related advice from a stranger’s entertainment-driven blog on the internet is very very very dangerous.

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