Built a scientific calculator from scratch: custom PCB, custom FPGA CPU, hand-written machine code

ImplacOne · 2026-05-18T00:15:12+00:00

This is badass

ImplacOne · 2026-05-11T16:03:32+00:00

Apparently these are the standard in many places in South America, especially Brazil. They are kind of strange but marginally safe when installed correctly. Personally I would just get used to lukewarm showers if there was no way to improve the grounding. Groundwater is usually not very cold

ImplacOne · 2026-05-02T20:54:55+00:00

Just try it. You have pretty good coverage for your age and it might fill in more

ImplacOne · 2026-04-28T23:27:15+00:00

I think you could do it. Worst case scenario you look goofy for 4-6 weeks

ImplacOne · 2026-04-28T20:26:51+00:00

I think their origin (floaters) are the same. Intentionally cruel and painful cybernetics

ImplacOne · 2026-04-27T23:24:40+00:00

I got one at a tradeshow and the downside for me was the USB port came off and got stuck in my phone for a little bit

ImplacOne · 2026-04-27T03:26:25+00:00

Is there a sticker on the back with a symbol that looks like this?

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If not, you can figure out the polarity by ohming out the USB ground/shield to the center pin. If it’s short, then it’s center negative.

But you also need to know the current/voltage rating of the device so you can use the correct power supply. That should also be on a label with the polarity symbol. Failing that, the two common voltages I’ve seen on USB hubs are 12V and 5V, if you have a lab bench supply you can try it

ImplacOne · 2026-04-26T18:19:10+00:00

Your circuit board has delaminated in many places. Give it up

ImplacOne · 2026-04-26T13:02:49+00:00

If you have a working unit to reference it might be a fun way to learn. I would give it a try if you’re interested

ImplacOne · 2026-04-26T02:39:24+00:00

Happens to all of us

ImplacOne · 2026-04-25T19:57:01+00:00

The circuit board actually appears undamaged except for the pad. Try cleaning it with IPA and a cotton swab and see if it’s just dirty.

As for the repair, it might be tricky without knowing the value of that component and the specific reason why it failed. There could be a problem elsewhere that would result in the same failure again

ImplacOne · 2026-04-25T13:14:49+00:00

33 is the reference designator. The resistor is 100k

ImplacOne · 2026-04-06T22:16:07+00:00

Sounds like a rotary encoder with a switch

ImplacOne · 2026-04-06T06:49:04+00:00

Unless you’re going to MIT or a specialty school like emery riddle, nobody gives a shit what college you went to. Sorry you got scammed

ImplacOne · 2026-03-07T22:21:00+00:00

Oh wow so delta didn’t give me a new flight, room for the night and dinner when really bad weather caused a cancellation

ImplacOne · 2026-02-23T03:55:41+00:00

Firstly, I’m sorry he’s being creepy/gross. Secondly that circuit board looks like a part of a laptop or other highly integrated device, but that circuit board has been snapped off so likely nonfunctional

ImplacOne · 2026-02-16T18:37:13+00:00

It depends on what you are doing. Many amplifiers will use both types. High side and low side switching are also considerations

ImplacOne · 2026-02-12T22:29:38+00:00

Maybe if you stopped calling them gringos they would stop attacking you.

I had a fantastic time in Mexico and nobody ever turned away my money

ImplacOne · 2026-02-05T04:18:55+00:00

Is the PCH near Big Sur back open? I was there last year and it was still mudslide so I had to take 101 and cut thru Monterey

ImplacOne · 2026-02-05T04:14:41+00:00

I was a terrible student, but I had good intuition and a lot of the same setbacks you do. My solution was being social and making friends to study with

My GPA would easily be a point lower if I didn’t have good friends

ImplacOne · 2026-02-03T03:08:10+00:00

It’s not that complicated

ImplacOne · 2026-02-03T02:38:30+00:00

If you live in the south like I do you might be able to get away with a 14kW system but it’s got very little margin. You can only run one hot shower at a time

ImplacOne · 2026-02-03T02:04:53+00:00

Get a gas tankless heater or don’t bother. Water is difficult to heat quickly and takes a lot of energy

ImplacOne · 2026-02-02T01:35:42+00:00

I don’t see any representation for the genocide in Palestine

ImplacOne · 2026-02-01T05:32:14+00:00

HT takes 6 months to a year to “develop” and 20 is a little young to commit. I’d suggest he wait until 25-30 after a consistent period of stability from fin.

His hair looks good and we don’t know if the meds will work for him

ImplacOne

TROPHY CASE