Notices by joey castillo (joeycastillo@mastodon.social)

“We didn’t design them to last 30 years or 40 years. We designed them not to fail.” https://www.smithsonianmag.com/smart-news/voyager-1-breaks-its-silence-with-nasa-via-a-radio-transmitter-not-used-since-1981-180985399/

Welp. One year late, I managed to get my @hackaday #supercon badge hack working, just by looking at it with fresh eyes for 15 minutes. The thing that kills me: I designed the hardware right, and I got it built in time, AND the software was essentially correct. If not for a one-bit configuration error, I could have presented this demo on stage.

AI, ladies and gentlemen!

“Your order includes a white friend device and a white case.” I mean, the jokes write themselves. https://www.friend.com/product.html

a (human) friend texted me this link with the question “is this real?” and maybe I’ve been in the mountains for too long but it can’t possibly be real, right? Like as a critique or a satire it’s both incisive and clever, but as an earnest attempt at a product it’s just… deeply unhinged?

“When will I receive my friend?”
“Pre-orders will start shipping Q1 2025.”
Questions frequently asked by the utterly deranged. https://www.friend.com/product.html

wow okay apparently it’s real, and they raised $2.5 million dollars, AND they spent $1.8 million of those dollars buying the domain name friend-dot-com, which is downright hilarious. I just spent $1.99 on the subway ride home buying the domain “enemy.lol”; anyone with web design chops wanna get in on this? I think “enemy” is a AI pendant that texts you to poke at your deepest insecurities. (with a premium plan it'll send your friends recordings of you talking about them behind their backs)

New battery test, day 625: 2.89 volts. Technically day 626, and probably closer to 2.885, but I intended on logging every 25 days, so there you have it. Ben reports from Paris that his watch (yellow line) died just a few days ago, which I think means I can estimate battery life between 1.7 and 2+ years, depending on how my watch does.

New battery test, day 873: it's over! Feels poetic that the battery died at #HOPE. (Also I was demo'ing it all afternoon at the @crowdsupply table.) I actually logged the battery yesterday at 2.19 volts — low enough that the LAP indicator was on, which meant the battery was on its last legs. Point is, the February 2022 firmware lasted 2.4 YEARS on a single 100 mAh coin cell, which is not bad! I'm now ready to claim 1.7 to 2.4 years of battery life — and that's backed by real-world testing :)

New battery test, en route to @crowdsupply #teardown at day 850: 2.52 volts. I missed the check-in at day 800 (2.72 V) but the trend line is clear: it’s going down. Probably 8% of charge left. I’m guessing I’ve got another 74 days on this coin cell, which puts it dying in early September. With some luck — and a lot more hard work — I might just have Sensor Watch Pro ready by then. 🤞🏽

New battery test, day 700: 2.84 volts, as I extend the X-axis another hundred days.

I now have enough data to posit that 2.85 volts is the 70% mark for battery exhaustion: old firmware hit it on day 300 and died on day 425; Ben's watch hit it at day 440 and died at day 622. By that math, I predict 292 days remain, for a death date around November 8th. Which means this little watch that could might just make it to its THIRD @hackaday Supercon on a single CR2016 coin cell.

New battery test, day 675: 2.85 volts. Number hold steady! Tho I admit I've been on and off with this watch the last few weeks; I've been splitting my time between Sensor Watch and a stock Casio W800H, just to get a feel for a larger watch on my wrist. Anyway, onward to 2024!

New battery test, day 650: 2.86 volts. Number go down! But even when number go down, watch can still function just fine, down to 1.62 volts (which realistically we won’t get to until the battery has but minutes left). If I had to guess, I’d guess I have 30% of my CR2016’s capacity remaining, which means we should easily make it to the two year mark, and I should be able to wear it all semester and well into the summer. If I’m being bold? I think it‘ll tick from February 2022 to September 2024. 🤞🏽

@derek I have one that I’m pretty happy with, but alas I’ve been so busy with teaching this semester that I haven’t had a chance to put it in the repo. I’ll try my best to make some time to uploaded it this weekend or next.

working on my week three lecture slides, on transducers and sensors, and once again I'm going hard. Just finished a photoshop job on a classic illustration; Thanks, Phototransistor Man!

no matter what safeguards you try to build to help internet users, the modern web is enough of a cesspool that some asshole is going to come up with something like this.

My sister got me circuit board socks for Christmas and I’m relieved to discover that they are, in fact, CE marked.

@josecastillo Battery test, day 380: 2.59 volts. To reiterate the parameters of the test: this watch (red line on the graph) is running an old firmware from 2021 that lacks some low power optimizations I did early this year. I also started a new watch (green line) in February of this year that I've been wearing daily since; it's still sitting pretty at 3.08 volts here on day 275.

I'm going to post a Sensor Watch battery update later today, and this post is to connect it to the old battery test thread. If you're new to this: in late 2021, I put a fresh coin cell into Sensor Watch, my board swap for the Casio F-91W wristwatch. This month that watch hit one year on that same battery, and in this thread I'm tracking how long the battery will last. You can click the “Replying to @josecastillo” link repeatedly to get back to the beginning of the test. https://twitter.joeycastillo.com/josecastillo/status/1590059216798388224/

@josecastillo Battery test, day 410: 2.195 volts. (Mostly 2.19, but it did hit 2.20 once). No more big voltage drop when I press the mode button, which signals to me that its steady state current consumption is higher now. That and the steepening of the red line 😬. This microcontroller operates down to 1.62 volts, which gives me optimism that this watch with the old firmware will still be with me in 2023, if only for a few days. (New firmware, green line: 3.07 volts at day 305.)

@josecastillo Battery test, day 400: 2.4 volts. It’s low enough now that the extra power of beeping the buzzer on mode change causes a voltage drop to ~2.3, but it recovers to 2.4 over about ten seconds. New firmware is back up to 3.08 volts here on day 295! Both lines are red this time, but it’s the one on top.