Tiny logic probe

[Ljmnunes]

Hello guys!

I read here people talking about Logic Probe.

So, I remembered that I built a very simple logical probe when I learned about digital electronics in the 1980s.

I challenged myself to make a logic probe that doesn't light up when the tip is floating and make it as small as possible. Yes, I'm a fan of miniaturization...

So, I bring it to you as it is. I redesigned it from memory because I lost the original and it schematic, so without guarantees, I haven't tested it, but you can easily modify it. If you make any changes, please forward them.

Later, I added a led to indicate pulses. This scheme does not have this function. I can't remember the circuit. I'll update it if I remember.

It is draw in Kicad and pdf too.

Enjoy.