Reddit:Electronics

Finally took the plunge and started to solder NOT, AND, and OR gates onto perfboard. Breadboarded an XOR this evening which I got working without frying anything too! Used 2N7000s for all of these (please don’t attack me for forgetting gate resistors). I’m super excited to start expanding into more complex projects soon!..

I’m pretty sure it’s just incandescence, but the behavior of it feels odd— it only glows above 9 volts at which point current will pass and it immediately reaches full brightness— no fade-in. If I didn’t know better I’d say it acts like an LED. My guess is that it’s just reaching some breakdown voltage and after which it passes current and glows.

Current passed from base-collector. Draws about 300mA at 20 volts.

And yes it was already blown— no live transistors were harmed lmao

Last pic is the original IC that I turned into a pin-compatible IC with the ATtiny45. Figuring out the pin mapping was a fun challenge. All the code is mine, including the IR decoding which took me 3 iterations to make it reliable and non-blocking. My plan is to eventually use a better wireless comm technology than IR :)

See how to make a simple 4 bits short register on Logisim

Flex in the comments⬇️

The Varactor diode in the photo seems to have marks of overheating.

I came to this conclusion after observation with a flashlight on the back of the board.

I was led to perform this visual inspection because I concluded that a stove's control board 098-01540-35 won't turn on due to a faulty G5Q-14 relay.

I'll add more findings down the road of troubleshooting.

Just got my new peak transistor tester and showing and old vintage one from a long dead friend of mine.

Photos 1, 2: Ч1-40 (Ch1-40) DOCXO quartz frequency standard.

Photos 3-6: В7-34А (V7-34A) Digital voltmeter. 5.5 digits. Features ovenized voltage reference, fully isolated and hermetically sealed analog part.

Photo 7: С1-107 (S1-107) Hybrid portable oscilloscope/multimeter with multimeter part drawn directly on the scope tube.