[HN Gopher] Thermochromic Breadboard
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Thermochromic Breadboard
Author : zdw
Score : 119 points
Date : 2023-07-08 13:10 UTC (9 hours ago)
(HTM) web link (www.improwis.com)
(TXT) w3m dump (www.improwis.com)
| HeyLaughingBoy wrote:
| > often happens that a power rating of some part is exceeded
|
| If this is happening more than rarely, you are really doing
| something wrong. Or you're prototyping a high power circuit and
| expect some mortality.
|
| Still, understanding the power dissipation of every component in
| your circuit should be second nature.
| TaylorAlexander wrote:
| Exceeding the power rating is more avoidable but sometimes I
| just get a footprint wrong or make a schematic error and I love
| my thermal camera for diagnosing that!
| paulmd wrote:
| What's good for thermal cameras these days? There is some
| cheaper stuff iirc but in general the resolutions are just
| kinda sad (32x32 or 64x64) unless you go to expensive gear.
| And even then it's like, 256x256, not exactly the 64-100+
| megapixels we get in traditional photography. I know you
| don't really _need_ it but it 's nice to have good gear.
|
| iirc some of the phone stuff was like a couple hundred bucks,
| which is definitely within toy-money range and I'd get some
| use out of that even with lower resolution. Anything notably
| great for, say, under $2-3k that'd be worth jumping to over
| something basic? That's not a number that I'm unaccustomed to
| with higher-end photography stuff if it's worth the spend.
| TaylorAlexander wrote:
| Depends on what you need it for but I have a ten year old
| FLIR i3 with 64x64 pixels. It's fine but the feature I
| would really like is that newer modules have both a normal
| camera and a thermal camera and they overlay the color
| image and the thermal image. That makes dealing with the
| low thermal resolution WAY easier since you can actually
| see which thing is hot. If you have a bunch of similar
| shaped chips on a board and all you can see is some
| rectangle is hot, it takes a moment to figure out which one
| you're looking at. (I do this by covering each chip with my
| finger and seeing when the image is occluded).
|
| So you don't really need high resolution for most stuff if
| you have the color image overlay. I haven't shopped for
| them in the last ten years before those types were common
| so I don't have a specific part to recommend.
|
| The thing is they are a fun toy but sometimes I question
| whether I should have spent $1500 on mine. I would suggest
| going on the cheaper end, not chasing specs for no reason,
| and just get the value out of it without breaking the bank.
| They're neat but for my use case I've never felt like I
| really needed to have it. If there's something that's $300
| go for it.
| jmgao wrote:
| I've been researching this recently because every time I
| need to use my FLIR One, it's annoying because I need to
| find it, charge it, plug it in, and use FLIR's awful
| software. In the last few years, a Chinese company started
| selling sensors that seem to be far superior to anything
| you can get for reasonable prices from FLIR (256x192, and
| 25Hz since they're not subject to American export
| controls). I've been looking into buying a Android phone
| with one of their sensors built in as a replacement,
| because it seems to have a lot of advantages:
|
| - not needing to futz with a dongle, way better displays
| than the standalone camera options
|
| - never needing to charge it if you leave it on a wireless
| charging pad
|
| - lots of internal storage that can automatically sync
| captured videos/pictures to the cloud
|
| There's tons of options that look great in the $300-$500
| range, which is a problem because it makes choosing
| difficult. This review has me leaning towards getting
| either a Doogee S98 Pro ($270), or a V20 Pro ($330, newer
| and has better specifications across the board except for
| not having wireless charging, so I'd need to get a wireless
| charging adapter for it):
| https://www.youtube.com/watch?v=4002_MqVNfY
| bbrks wrote:
| I don't have any PCB shots but I have some sample ikages
| from a cheap Noyafa which does 160x120 on my blog. The next
| model up (also much cheaper than FLIR equivalents) claims
| double resolution at 256x192
|
| https://bbrks.me/noyafa-nf-583-review/
| Hextinium wrote:
| I have used a FLIR TG267 at work to find if parts are
| failing and while it's only 120x160 it works pretty well
| because it can overlay thermal coloration over a standard
| camera which really lets you use those pixels for
| temperature not identification.
|
| This lets you know "ah this transistor is dead" instead of
| "what I am I even looking at".
| obrajesse wrote:
| A tool like this is a fantastic way to help it to become second
| nature
| nunuvit wrote:
| All you have to do is read the datasheet and multiply a few
| numbers to calculate worst-case power. Remembering to do that
| should be second nature, like remembering to close any
| parentheses you open. It's a great tool for understanding in
| greater detail, but it's not the way to avoid breaking stuff.
| serf wrote:
| if I was to give a kid a breadboard and a bag of components
| I wouldn't want them to avoid breaking stuff; what I
| _would_ want is for the child to be able to interpret the
| event and gain knowledge from the mistake.
|
| This idea can shift the paradigm from "oh, the LED doesn't
| work", to "Oh, the LED doesn't work, the color around that
| rectifier area has shifted; why?" , and I think that can
| help to build intuition.
| nunuvit wrote:
| So teach them to check the power and the paint will help
| them realize when they forget to do so.
| rpearl wrote:
| what precisely is wrong with visual feedback?
| nunuvit wrote:
| Nothing. It's great. But it's the wrong tool for the job.
| Like teaching someone to stop a car by using the
| speedometer to estimate when to let go of the accelerator
| pedal, instead of introducing them to the brake pedal.
| viraptor wrote:
| "You won't make mistakes if you remember not to make
| mistakes" is nice in theory, but just not how people work
| in real world. Just like trivial syntax errors are very
| common while you're doing things. It's better to embrace
| the common human failures and have a second layer of
| protection.
| nunuvit wrote:
| I explained in my other comment that it's a great tool
| for other jobs, but the wrong tool for this job. You
| won't learn how not to break things by using it.
| Avicebron wrote:
| [flagged]
| lloydatkinson wrote:
| What does that even mean? What a dumb comment
| ComputerGuru wrote:
| In case anyone has trouble getting the link to load:
| https://archive.is/zO7dg
| ComputerGuru wrote:
| Call me old school, but licking the tip of my finger and
| carefully touching parts has worked for me in the past! (You
| usually get a sense for which parts are the most likely to
| generate heat fairly quickly, so it's just a matter of
| confirmation.)
| RicoElectrico wrote:
| Some 15 years ago I had a breadboard with CMOS 4000 logic chips
| connected to a power supply, left the room and came back later to
| see it dead. I saw some faint burn marks on the breadboard.
|
| I never figured out what caused this, but 99% it was my little
| brother swapping banana plugs to the supply. CMOS chips don't
| like that as ESD protection diodes are put in forward mode
| conducting a lot of current. Depending on power capacity of
| supply they may or may not survive.
| amelius wrote:
| This is why a thermal imaging camera is a good idea.
| HPsquared wrote:
| Multipurpose, too
| Groxx wrote:
| This was my thought too. The paint is a neat low-tech
| technique... but thermal imaging is cheap and _hundreds or
| thousands_ of times faster to respond. Plus it 's infinitely
| reusable, and works on any board type (it doesn't even require
| a board).
| [deleted]
| nosmokewhereiam wrote:
| The bitunlocker TTP may apply here; spray the board with
| upsidedown canned air to freeze traces and see where things thaw
| fastest.
| CamperBob2 wrote:
| Yes, or spray with alcohol and watch the evaporation.
|
| Both alcohol and freeze-spray have the drawback of condensing
| moisture on the board, unfortunately, which can be problematic
| in high-impedance circuits. Not all of those are obvious; e.g.,
| the voltage divider in a typical switching regulator reference
| design that's been optimized for efficiency. A combination of
| moisture, flux residue, and a 1M+ resistor can do (not-so)
| funny things.
| hcrean wrote:
| That is a clever idea, but I tend to find overheating is too
| sudden to notice from colour changes.
| chongli wrote:
| Yeah, this is why a cheap thermographic camera is a useful tool
| for electronics tinkering.
| dghughes wrote:
| > a cheap thermographic camera
|
| Define "cheap" and where would one come across such a beast?
| I'd like one but they tend to be expensive. Add-on IR modules
| for phones are OK but ports change and standalone devices are
| double ($600 CAN) the phone add-on modules ($300 CAN). Sub
| $200 CAN would be nice.
| anfractuosity wrote:
| This one looks interesting -
| https://hackaday.com/2023/06/19/review-infiray-p2-pro-
| therma... the fps seems reasonable too.
| viraptor wrote:
| You're going to be ok with the current USB-c for many years
| now, so that should solve at least one issue.
| CamperBob2 wrote:
| You can buy one for less than a smoked PCB typically costs.
| It's scary how dependent I've become on my FLIR E4.
| rpearl wrote:
| I've made a couple dozen pcbs of varying complexity in
| the past 6 months and I still haven't spent more than a
| FLIR E4 would cost ??
| prashnts wrote:
| At one point my laptop had some thermochromic indicators to
| indicate when the laptop became warm. I salvaged it from dead
| duracell batteries (ones which have a battery level indicator). I
| noticed that it's too slow to react though.
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