Help with p100 from www.generalguitargadgets.com

[duclon]

hi, I'm building the p100 kit from www.generalguitargadgets.com and have an issue with it. Heres the scoop. I've built the project, and really taken time and have it exactly to specs with the supplied parts. before I tell the issues, I'll say, I've check ed every solder joint with an eye loop, looked it over closely, so i think I did a good job assembling the unit, at least my father who is an electronics teacher passed my work  So here is the issue. I hooked up the 2 poll 6 POS switch , i wasn't sure exactly how, because the switch given in the parts list was a 2 pole 4 pos switch, so I used the logic from this pdf, which uses 2 switches instead of the 4 POS switch.
http://www.generalguitargadgets.com/pdf/ggg_p100_lo_2.pdf
the issues I have is, If I short out the sw3 leads which are purple and orange, I get a loud siren, squeal. Really bad and loud. If I leave it open then no problem. So I think there must be a problem if this sw3 is supposed to work in the shorted setting. here is a picture of my board not that it will help. The red line is showing the wires that go to sw3 and cause the issue. this same thing happens when I wire in the rotary switch, that's why i removed it to test.
http://www.softseas.net/p100.htm
Did I fry something? Does the circuit not work?
Any help will be appreciated.
Mike

[jsleep]

Hi Michael,

I'll post a photo diagram of the wiring of that rotary switch.

The switch is a Lorin "user adjustable" rotary switch , which means that you can use the little collar around the pole to adjust the number of positions on the switch (between 2 to 6)  in this case it should be set to 4 positions.  A clear photo of the back of the switch should clear things up I think.

JD

[duclon]

Thanks JD

[duclon]

Hi, JD, I didn't see a picture posted anywhere, but I thought I'd save you the trouble. In my post i wasn't too clear, but i did figure how to wire up the 2 pole 6 position switch. i used my ohm meter and did that, but like I said the issue is when I short the purple and orange wires, it sounds like a siren. that would be a cool effect, but not what I'm after. So if i leave those leads open and short the brown and gray, the i get 2 nice phase sounds, one with those two wires open and closed. So it seems that if I have it wired correctly, I'm pretty sure I do having looked it a bazillion times until my eyes popped out of my head, that I must have something bad, either that I fried or from the get go.
The sixty four dollar question is, what could be bad, or mis wired, and how do I detect it? Do you think I fried an IC or something?

Thanks
Michael

Hi Michael,

I'll post a photo diagram of the wiring of that rotary switch.

The switch is a Lorin "user adjustable" rotary switch , which means that you can use the little collar around the pole to adjust the number of positions on the switch (between 2 to 6)  in this case it should be set to 4 positions.  A clear photo of the back of the switch should clear things up I think.

JD

[jsleep]

Michael  (and anyone else with a P100 kit)

The loud siren sound on the two settings that add in the "regeneration" can be fixed by raising the value of R1.  I'm very sorry I didn't catch this sooner, on the two prototypes that I built I didn't have this problem.  The problem can be solved by changing the R1 value to around a 30k resistor.  I'll be adding an extra 30k resistor in with the kits from now on.  I was able to get my hands on a P100 that was oscillating like this and verified that the 30k R1 fixes the problem and as far as I could tell did not diminish the sound quality at all.  Again, I apologize for taking so long to get this solved, I was unable to duplicate the problem until a couple days ago.  If anyone else here bought a p100 kit, let me know and I'll send you a 30k resistor real quick.

JD