Thread that errored out:>>2964845>I'm new to electronics. Where to get started?It is an art/science of applying principles to requirements.Find problem, learn principles, design and verify solution, build, test, post results, repeat.Read the datasheet.>OP source:https://github.com/74HC14/ohmOPbake at page 10, post in old thread>Comprehensive list of electronics resources:https://github.com/kitspace/awesome-electronics>Project ideas:https://hackaday.iohttps://instructables.com/tag/type-id/category-technology/https://adafruit.comhttps://makezine.com/category/electronics/>Books:https://libgen.is/>Principles (by increasing skill level):Mims III, Getting Started in ElectronicsGeier, How to Diagnose & Fix Everything ElectronicKybett & Boysen, All New Electronics Self-Teaching GuideScherz & Monk, Practical Electronics for InventorsHorowitz and Hill, The Art of Electronics>Recommended software tools:KiCAD 6+CircuitmakerLogisim Evolution>Recommended Components/equipment:OctopartLCSCeBay/AliExpress sellers, for component assortments/sample kits (caveat emptor)Local independent electronics distributorsladyada.net/library/procure/hobbyist.html>Most relevant YouTube channels:EEVblogW2AEWMoritz Klein>microcontroller specific problems?>>>/diy/mcg>I have junk, what do?Shitcan it>consumer product support or PC building?>>>/g/>household/premises wiring?More rules-driven than engineering, try /qtddtot/ or sparky general first>antigravity and/or overunity?Go away
>>2970026>>antigravity and/or overunity?>Go awaynot electronic, but i have a client that really thinks he devised a piston pump that can works without energy just playing with peresure references.I am being paid on explaining him why it doesnt work
Made new circuit using PNP transistor, 74hc14 and a 555 timer, now I have solid, single, 1.2ms pulses everytime the ignition sparksStill got a lot of noise on the power line (green) I'm trying to figure out how to stop, I think that's what's corrupting my SD cardIt's 70% less noise than it was so I'm making some good progress, the scope was worth every penny
>>2970100>74hc14 schmitt triggers have saved my ass on numerous occasions as welland, being pin compatible with the 4069, a fix can often be done in 10 seconds with a chip swap
>>2970100This circuit is working well on the bench, adding and changing shit on the bread board didn't realize d2 and d2 were basically doing the same thing, oh wellSome nasty voltages even spinning it with a drill, like +/-10v, it's pretty grossGonna bring the whole ass scope to the track tomorrow for some fun adventures
>>2970195>didn't realize d2 and d2 were basically doing the same thingim assuming you meant D1 and D2. D2 has R4 in front of it so theyre not exactly identical, but neither of them are protecting the schmitt trigger since theyre both behind the coupling cap.when the base of Q1 jumps really high, the BE junction becomes reverse biased and you can break it pretty easily, often just a few volts of reverse bias.move one of the diodes to the base and tie it to +3.3V to prevent the base from going much higher than that. move the other diode _behind_ the coupling cap.also, dont leave the input of the schmitt trigger floating like that. tie it to ground with a 1 Meg or something.
>>2970201>since theyre both behind the coupling cap>move the other diode _behind_ the coupling cap.or in front, idk you know what i mean.
>>2970195Yeah D2 is useless.You probably want a diode in anti-parallel with Q1's BE junction, to clamp voltage spikes that are above 3.3V. Probably the good old 1N4148. Don't know if R1 is necessary, BJTs don't really parasitically turn on like FETs do.After C2 there's no DC reference, I'd consider adding a voltage divider or clamping diodes to hold it in place, if not both. A voltage divider is definitely a good idea as it will bias your schmitt trigger to relax into its hysteretic zone, something like a pair of 10k resistors, one to Vcc and one to GND. R5 is pointless since no significant current should be going into U1's input, unless you're relying on its built-in clamping diodes (bad practice, especially in an automotive environment). Either way, consider adding a pair of proper input clamping diodes, again 1N4148s should work well. Just one clamping diode is probably fine, assuming Q1 remains operating as normal.D3 and R6 are even more useless than R5.FYI you can make a monostable circuit like this solely with schmitt inverters and high-pass filters, but they're not as reliable or well-tunable compared to a 555. Something to consider if you want to use less parts. You could also use a comparator instead of a logical inverter, that would allow you to set the hysteresis wider or narrower as desired. You could also swap to 12V tolerant parts, just to make the system more electrically robust.
>>2970203>Don't know if R1 is necessary, BJTs don't really parasitically turn on like FETs do.R1 ties the base to DC.
>>2970205R1's integral base-emitter diode does that well enough. The resistor makes it slightly harder to turn on if anything, which is probably a good thing, but I don't know if it would be noticeable.
Finally found a piece of software to diagnose RAM issues with my GPU and had to register on a some Russian forum to actually get the links. Registration process was "unique". kek
>>2970201>>2970203Thanks for the tips guys, time to do some playing around
>>2970246That's a big oofUpwards of 1v swings on the power lineThis is the original circuit, let's play around now with what y'all saidNo I don't know why I placed the power line (green) where I did, cope with itIt's going from like 3.1 to 3.9v
>>2970247Need bigger PSU capacitors, maybe even chokes. And depending on whether you’ve got magnetic or electric field noise, the mitigation strategies will change. I’d consider having a coaxial wire with 3.3V shield going from the antenna to the BJT to take the rest of the circuit further from the engine, and putting some ferrite beads around the coax.You might have less noise if you use an NPN relative to ground instead, maybe,
My custom small home water heating system, fully electricI don't care about efficiency because I have plenty of spare energy from solar.
>>2970268
>>2970268last one
>>2970268>>2970270>instant water heaterSo, do you buffer the energy with batteries if you don't have a hot water tank?
every few weeks I have to replace one or both of these caps in this shitty peltier fridge for my nephew. Everything else behaves as it should so I'm wondering if you guys have any advice. I replace them with equivalent caps from amazon (but maybe theyre shitty chinesium caps?) could I replace them with something more robust? If all else fails I will just replace the entire board with a random 120->12v power supply board. There is a weird 'burnt' or hot spot by the transformer also so I'm not sure what that could be
>>2970283Double the voltage rating on the caps if there's enough room, and get high-temp ratings because they're right next to a heatsink. A smol fan would help extend their life. You could also lay them flat and solder them to the bottom side of the PCB.
>>2970285Almost forgot- never use chink caps in anything you care about.
>>2970285thats a good idea, never thought about the heat from the heatsink. The ones I am using are rated for 105C, could it be getting hotter than that? I'll try it though, thanks
>>2970287It's probably not getting that hot, but 125C rated capacitors (of reputable brands) are better able to handle sustained periods of heat.
>>2970290and you might want low-ESR caps depending on the switching frequency of the PSU.
>>2970283Buy a compressor fridge 2nd hand. Peltier fridges are rarely worth using, a single-can thermoelectric fridge churns through as much power as a full-size upright fridge.
