/diy/ - Do It Yourself

>>2495629
>>2495642
>not making breakout boards for repetitive shit
>not adding transistors to take the load off of I/O pins

>>1956807
I've been working on this in KiCad. I just got tired of making this circuit all the time. It's not the first time I've done something on a side board like this, I guess you could call them "breadboard macros". The other day I did a similar thing with a MIDI DIN plug, and I'm about to make another.
I had already built a prototype on perfboard, and I found out that it's not only useful directly on a breadboard. I stuck a bunch of dupont fly wires on it and was able to use it to debug a project.
The circuit is basically 1.4K resistor -> 2N3904 open collector -> LED with 120R resistor.
The values were chosen because I already had a tape reel of each resistor, and a bunch of loose transistors. The holes are to mount it on a front panel with a ribbon cable. Also my original had the pins 0.2" apart to line up on the perfboard.
Now I'm looking for somewhere to get them printed up. Depending on the minimum size I might panel them 2-up. I think 2"x2" (50mm) is often a minimum size before the cost starts going up, and these are slightly smaller than 1x1.75.