fuzzonaut wrote:Amazing stuff on those last few pages!
It's been raining the last two days, so I've just finished another Deadend FX PCB built. It's their take on the Silver Rose. It was quite a tight fit. I usually solder just one or two pots to the PCB and wire the rest, because I'm drilling by hand and am usually not too precise while doing it. And I usually use bigger knobs, so spacing them out is cool.
This time though, all knobs but one (Master) and the 3 switches were pcb mount, so yeah, I'm just glad I got it in there.
It works alright, but while testing it, I observed something rather baffling: when the pedal is bypassed, the mids switch (upper right) turns the pilot light off and on - but that's not all, the Mix knob (Fuzz Mix) also acts as a dimmer, meaning the light gets brighter when I turn it clockwise (to the Superfuzz side) and it goes out when I'm halfway into the muff ......
That happens no matter if I've got something plugged in or not.
Anybody got an idea what's going on there?
One of the pilot light wires touching something?
But anyway, it rips big time, so I guess I'll just leave the dimmer mod as is.
Silver-S.jpg
SilverS.jpg
Def not normal insofar as the LED is concerned.
First and foremost, I see that you're using sockets for the BS170 and 2N3904. If you're not getting good contact between the pins and sockets, then the Mill2 may act wonky, as it is now. Leave as is for now, and read on...
First, check R11. It should be 100K.
Second, what MOSFET did you use for the Mill2 bypass? I've had a bum BS170 do that to me in the past. You can sub a 2N7000 in there as well,
but you have to turn it around 180 degrees (opposite to the silkscreen outline on the PCB). Generally, either BS170 or 2N7000 will work equally well, though on rare occasions, I've had a 2N7000 work better. I generally always use 2N7000's, but that's me. Since you have sockets in there, you can test. Try another BS170, or swap in a 2N7000 instead (observe aforementioned warning in bold italic!).
Also, check to see if the diode D11 is good, use the diode function of your DMM. Ultimately, on the fringe, the transistor (2N3904) might be suspect. Again... sockets are there, so test. Just about any NPN transistor should work here.
If one of the above turns up to be the culprit, then do yourself a huge favor, remove the sockets, and solder the components directly. That applies to all your other socketed components too. Sockets are OK for testing and/or auditioning, but once you've made your ultimate choices, save yourself from a shitload of headaches, and solder them in direct.