sunking help, With Voltages! (for real this time)

[jtn191]

Here's my switch, which I think may be the source of the problem.



Also as far as the pot wiring goes...does it matter which set is gain 1 and which is gain 2? Something weird I did (which may be cause for problem) is I soldered one of the wires to the metal ring near the lugs here

But I was pretty sure that doing so is the same as making a connection with the lug

[jkokura]

Yeah, your voltages look alright. I've not got a set of mine around to verify, but I don't see anything glaringly wrong.

As for your switch and wiring, yes it's probably likely there's a problem in your bypass or pot wiring. As mentioned, an audio probe would be a helpful tool right now. Essentially, you need to start at the beginning (or the end) of your circuit, and then trace through to locate the beginning of the problem. Once we've found that, then we know how to fix it because we've located at least the start of the problem.

Is that understandable?

Jacob

[jtn191]

Ok, I bought parts for my audio probe and put it together. It's a mono jack...sleeve to ground of pcb, tip to .1uF film cap and used as probe

I was testing the input jack during bypass...and I was getting a fuzzy, arpeggiated decay signal. any ideas?
I tested the effected signal too and got oscillations even on the input jack. methinks the problem is wiring at the switch?

And for clarification: in the build docs, the dpdt lugs should connect vertically, correct?

[jkokura]

You DPDT switch is the x-wing type right? If it's to be oriented correctly, there would be three lugs up and down, and two lugs side to side. the middle pair is the common lugs, and then each side pair would be where the switch flips to.

My recommendation at this point is to completely rewire at least your switch. Perhaps you should also check through your jack and pot wiring as well.

Jacob

[jtn191]

well looks like Tayda Mammoth sold me bad [economy] jacks--the tips and sleeves weren't well isolated from each other...

[jkokura]

well, that happens. So it is it working now?

Jacob

[jtn191]

I replaced the economy jacks with normal ones I got from Mammoth a long time ago.
Now the hum is gone when the power supply is removed, it's back when the plug is inserted. I measured the resistance between ground and 9v and it is 100k--does this make sense

I'm at a lost--oscillation is still there and I don't have enough good jacks for a working audio probe.


edit: could a broken 1n39a be a possible source?

[gtr2]

It would still function without the 1n34's, it would just be raspy with higher gain settings.

It still sounds like you have a wiring issue...

Can you take some pics of everything?

[jtn191]

yeah I'll post some later.
I've broken 3 1n34as so far 

btw, doubt there's many wimin 'round these parts but happy mother's day

[bangerang101]

 Hey, don't know if this is of any help but... the wiring to your board in the picture you posted above looks really sketchy... namely that red one thats 3 down from the top... it looks like it's touching other components after coming off of the solder pad... IDK, just thought I would point that out.

[madbean]

I replaced the economy jacks with normal ones I got from Mammoth a long time ago.
Now the hum is gone when the power supply is removed, it's back when the plug is inserted. I measured the resistance between ground and 9v and it is 100k--does this make sense

I'm at a lost--oscillation is still there and I don't have enough good jacks for a working audio probe.


edit: could a broken 1n39a be a possible source?

No hum with battery, hum with PS. What PS are you using? This is pretty typical off the Boss type. Plus, they put out closer to 12-13v.

[jtn191]

No, there is no battery clip, so no battery at all. Here is everything explained more clearly:

When bypassed there is what sounds like 60 Hz hum and some guitar signal

When effect is "on" (IE LED is on):
-hum is louder
When Gain:100% Tone:0 Volume: 0%...I get a clean signal, similar to that when bypassed
When tone is increased, I get a bit of what sounds like a filter sweep, then an incredible high pitched squeal/scream when increased--which increases in pitch
When Gain is reduced, it sounds like a helicopter or machine gun "on/off" pulse wave

high res pics:





regarding parts/attempts:
-I replaced the faulty (?) mammoth economy jacks with standard ones
-I've broken 3 diodes--1n34as--and only have one intact on the board. They are incredibly sensitive when sliding into tight quarters
-The green electrolytic caps are mammoths "audio grade" cap. It's not so much that I thought they'd make much of a difference as "eh what the hell"
-I attempted to resolder/clean up some of the wires bangerang101 mentioned

[maysink]

Clip the excess wire from the top side of the pcb's gain pads--your photos look like they may be shorting? Also, you're melting the insulation from your hookup wire, especially around the switch connection on the 'bottom' of the pcb. I'd suggest quicker solder work on the wires or get some of the lovely teflon coated 22ga wire avail on ebay (it's the shit!)

Lastly, clip your component leads (resistor, capacitor, etc) a little tighter.

[rullywowr]

I'd suggest quicker solder work on the wires or get some of the lovely teflon coated 22ga wire avail on ebay (it's the shit!)

+10000000