So…I didn’t write up the PCB etching post yet because I decided to build this up instead and hopefully have a working circuit to show off at the end of that post.
It…didn’t quite go that way. Assembly went off fairly easily:
That one iffy spot on that one trace I patched up…but in the process created a bridge to the nearly ground pour. Fixed that but it left a bit of a “scar” since you can never get ALL the solder off of copper once it’s on there:
Drew up and panel and started printing it…but didn’t want to wait for it so re-used the first Steiner panel instead for now:
Plugged it in…and…I got nothing. Hmmm. Power traces checked out…maybe it’s like my #1222 and the fine tuning is just way out. Turned it a bunch in both directions. Still nothing.
Turned the volume way up and it was doing a bit of clicking. So…it’s not totally dead.
Took a look at the schematic again…and…found a mistake on the CV input circuit. Had a resistor in the wrong place. Whoops. Fixed it on the schematic and on the PCB design…then did the same fix on my board with some bodge wires:
Better. I’m getting SOMETHING at least now. It’s REALLY low frequency though and turning the adjustment trimmer just makes it get lower. The coarse tune and pwm knobs do make a difference…but something still isn’t right.
Took another look at the schematic. And…Yeah…I made some bigger mistakes on the CV circuit
Big enough to requite moving components and more than I think I can patch up with just some bodge wires. So…looks like I get to etch a new board tomorrow and move the parts over But I’m going to sleep on it first. I might be able to bodge this board into working first to confirm things. Just the changes are big enough that will be awfully confusing to implement.
And I want to take another look at the schematic and make sure I’ve got the CV inputs sorted out.
So big PCB post will hopefully happen tomorrow.