acetone FM-2 pcb

[imJonWain]

Does anyone know of anyone who makes/sells an acetone FM-2 PCB? I'm finishing up a vero build of one but would like do a PCB one...

[XIX tech]

There are many cheap board manufacturers in China and other countries. You only need a gerber files.
I can help with board design and production, just PM to me.

[imJonWain]

thanks for the offer but I actually just started working on a pcb layout during my lunch breaks at work haha. I'll probably have a few made and sells extras on here one I test em.

[Dr Satan]

You can always look at a SuperFuzz layout, it's basically the same thing with different value parts and a few minor changes. You could probably kludge one together on a SuperFuzz board without it being too wonky.

[imJonWain]

Any of the gurus/more experienced folks mind taking a quick gander and chiming in with any thoughts on my layout or if you see any mistakes? I help with PCB layout at work and
doing small power supply boards but this is my first PCB layout on my own. I was gonna do a top and bottom ground planes "just because", any reason not too? My minor experience is there isn't any price difference between 1 and 2 sided boards at least in China.

[crochambeau]

There's only a wiper lead to your volume?

On your schematic rendering there were incomplete leads between the tone and volume control, if you're wanting to wire that off board to allow for the different functions you mention, you'll still want to terminate those nets onto a pad, I generally grab single pin connectors when I do this sort of thing, but it's MUCH easier down the road if you draw everything correct and complete, and then shoot off some utility connection points in case you feel like getting kinky.

A poured ground plane is very good practice with a lot of high frequency stuff, not so much audio bandwidth unless your circuit is susceptible to RFI. That said, I have stopped doing them for the following reasons:

1) it's easier to inspect the board with the back light method if there isn't a wall of copper in the way.
2) it's easier to R&R parts that connect to the ground plane when there isn't a big thermal mass wicking heat on that pad, but I do a lot of fine tuning/value selection on a finished/early rev PCB as part of my prototyping work flow. This is probably not as large a concern on an established design... but it will also make repairs easier.

So keeping the copper fill is not a bad decision; HOWEVER, if you do I would highly recommend manually laying a ground trace before filling, as it makes spotting unassigned connections (like at tone & volume) easier.

[imJonWain]

cool, thanks for input!

[imJonWain]

Redux: Gonna double check them over now, pretty sure there aren't any mistakes. Decided to go with your no ground pour point after dealing with the annoyance of a massive ground pour at work Thursday.

[crochambeau]

Just to confirm, you're off board wiring the pots & R29, correct?

[imJonWain]

Yup to both, I just made an _external_ version of the resistor to use on the schematic. Oh I see what you meant before now, it is a waste/confusing to have the "extra" unused hole on the pcb and it isn't totally clear on the schematic...

[crochambeau]

Yeah, took me a moment to grock that, the PCB looks good (via my admittedly light once over). Look forward to seeing/hearing the results!

[imJonWain]

Just looking it over one more time I found a a pretty serious error in my schematic! haha oh well, differential pair was drawn wrong and wouldn't of worked... off to seeed we go now!

Thanks for the input!

[baremountain]

At a quick glance it looks well planned! I think you need to connect the center post on the Tone knob to something though, lest your pot act like a simple resistor

[multi_s]

^^what he said and also the VOlume pot is missing one of the nets it looks like from the PCB.

Actually it looks like the resistor that goes from the tone knob pad not connected to the volume knob pad not connected is not even on your pcb so maybe that is teh issue.

In summary: No R29 on pcb.

Is this kicad?

haha sorry i did not read the whole thread. looks nice.

[imJonWain]

Thanks! Yeah I decided just to use the 3 hole off board pot "package" from the madbean library even though some of the points will be unused with off board wiring. I woulda put R29 on the board but I figured this saved a little space and let people decide how they want to wire the tone/vol/fuzz controls on their own since stock the FM-2 is kinda wonky. Maybe I'll try a redesign with board mount pots at some point if it makes sense.