anetanel wrote on 2023-03-09, 08:47:

I tried looking for a replacement DSUB connector by selecting all the attributes and looking for similar, and the search came up with 20 items. Can I just grab the cheapest one? 😜

You can use the cheapest part that is genuinely equivalent. Make sure to check the position of all pads, including mechanical pads, relative to the edge of the board.

anetanel wrote on 2023-03-09, 08:47:

And can the amp chip be replaced with this one: https://www.mouser.co.il/ProductDetail/Texas- … i7hHRxlkw%3D%3D ?
I noticed that it have a bit different "Output Current per Channel" value of 20mA, vs 40mA in the original part.

The LM324 OpAmp is a rather generic part. The exact manufacturer is largely irrelevant because circuits using such a chip are usually designed with component substitution already in mind and do not rely on the minor differences.

LM324 is used in a lot of devices.
Pretty sure there be still a lot of those around even in 20 Years.
Its chip design from 70s

Thanks.
I actually got a response in the git repo as well, and he even updated the BOM.
It seems that for the DSUB, one critical dimension is the distance of the mounting pins from the edge of the board, which should be 9.5 mm.
Looking at the datasheets of the part I found, it seems that I'm all good 😀
https://b2b.harting.com/files/download/PRD/PD … 9804DRW001C.pdf

EDIT:
Actually I see that the updated BOM has a different, even cheaper DSUB. Hurrah!