I got a logic probe a while back but never got around to testing it. That was a mistake as it’s a brilliant tool for debugging your circuit. Until now I have used my trusty multimeter to check for signals when my circuit is faulty. But that’s a pain to have one eye on the multimeter display and one on the test point. With the logic probe it’s much easier, one sound (and LED) for a high signal, another one for low and a third for a puls train. If there is no sound the connection is either faulty, not connected or at high impedance.
So my tip is really to get yourself a logic probe, it’s worth every cent!
So I just finished one built around a TL082 OpAmp. I just googled for a schematic and built one I had parts for. As I was working, I was thinking about how much more I could test with a microcontroller. Maybe a poor-poor-poor man’s O-scope? Resistance, pulse length, high and low triggers of different sorts, timing events --all this could be done with a $5 Arduino and a cheap LCD.
Oh! Oh! Holy Geeze!! I gots me a LCDuino fresh from Mr. McCabe! Oh, I think I might just have to make a “logic box”! Maybe a cool probe with a high/low led around the tip? Audio feedback? Oh! So many ideas!!
