Mutilating a Porkbarrel

[DutchMF]

Now, before anyone starts about the rules for getting tech help, I need some pointers before I can give the required info...... Please read on!

I've built up a Porkbarrel with a load of mods. I put Brian's depth-mod on a switch, reintroduced the vibe switch and the mix pot and put 2 rate pots on a switch. It's an MN3207 version by the way. I did the two rate pot thing by attaching lugs 2 and 3 to a 3PDT switch, keeping both lugs 1 connected at all times and using the last pole of the 3PDT to switch a bi-colour LED. Everything works! Depth-mod on the switch is ok, mix pot works, but I don't like it to much, vibe switch works and I like it a lot, and even the 2 rate pots work, including the bi-colour LED! Why the hell is he posting a tech help thread then, you ask?

Noise!!!! A whole lot of incredibly huge, annoying clock noise!! So much actually, I didn't need to strum my guitar to check that all those mods were working.... 

What, and where should I measure, to get an idea of what is wrong? I specifically built up this MN3207 to test these mods, so I could use them problem free in an MN 3007 version... Any help would be greatly appreciated, thanks!

Paul

[DutchMF]

Bump, anybody?

[jkokura]

I got lots of clock noise, then I figured out that adjusting wires made it quieter or louder.

Try moving your wiring around and seeing if that does anything. I was able to eliminate all audible noise by rerouting wiring in a different pattern. Particularly with the pots.

Going to board mounted pots makes a big difference in eliminating noise.

Jacob

[DutchMF]

Thanx Jacob! I'll remove as much of the wiring as possible, but since I actually want to switch pots, I'm stuck to wiring at least the rate pot(s). I'll post some pic's of my prototype tomorrow, just for shits and giggles.....

Paul

[jkokura]

In case you missed it, what I was suggesting was that the routing of the wires themselves may be the issue, as in their location. Move your wires around and see if it helps or not.

Jacob

[DutchMF]

I got what you meant Jacob, but since there isn't much wiring (this was meant as a prototype to test the mods, so I mounted all the pots and switches on the component side, sticking up in the air, input and output wire in a straight line away from the board to the testing rig) I think removal is the only option... Sadly I don't have time to mess with it today, as I promised my wife to take her to Amsterdam today (which is fun, don't get me wrong....  ) I'll experiment some tomorrow and report back.

Paul

[bigmufffuzzwizz]

IMO this circuit needs that depth mod (c18 47pf) hardwired. It sounds kinda thin without it, so I just bumped that value up to 100pf and left it alone. In conjunction with MB's Led indicator depth mod I get so much warble! Also if you don't like the speed parameters on the rate knob adjust c20. 10/22nf will be super fast, 100nf will be normal and 220 will get you slow range territory.
As for the noise i don't have much of a solution besides trying to trace where its coming from..

[claytushaywood]

I know this is an oldy- but im currently in a pork barrel build...

curious what youre referring to with the c18 47pf mod...?

IMO this circuit needs that depth mod (c18 47pf) hardwired. It sounds kinda thin without it, so I just bumped that value up to 100pf and left it alone. In conjunction with MB's Led indicator depth mod I get so much warble! Also if you don't like the speed parameters on the rate knob adjust c20. 10/22nf will be super fast, 100nf will be normal and 220 will get you slow range territory.
As for the noise i don't have much of a solution besides trying to trace where its coming from..