tonebender ? collector voltage on Q3

[donald stringer]

I currently have a working version of this circuit on the breadboard http://fuzzcentral.tripod.com/benderII.html    My question is why cant I get the voltage down to the 4.69 on the collector of q3 using a 25k trim[thats the closest that I have to the20k that phillip recomended. I have tried all types of trimmers but the closest I get is about 6 volts. The circuit works fine with the 8.2k resistor but before I build it I was wanting to try all possible mods first. I am using oc128 -01. Common sence tells me that a 10k trimmer should be sufficient. Overall the circuit sounds great but I want to tweak the tone a little.

[MartyMart]

Donald, I'll presume that you have it wired correctly ? ( backwards? )
I've had a few "bad" trimmers ( cheap ones! )
could be just that, remove it and check that it is working with your DMM?
Your right, a 10k trimmer should work fine, but it depends on the
transistor too .....

Marty.

[donald stringer]

Here is whats happening so far. All I had for an attack pot was 5k, when I replaced it with a 1kresistor that allowed me to get the collector voltage down to 4.69. So if you use anything higher than a 1k pot or resistor that directly effects the collector voltage. But I still have to use a 100k trimmer. One more question, do you connect the ground connections from the input and outputs to the positive ground side of the circuit or the collector side of the circuit?

[MartyMart]

I see, this should help to get you out of trouble :
Either, put a 4k7/5k6 resistor across your 5k pot, lugs 3 to 1 - I've done
this to quite a few FF's when I have only a 4k7 pot for gain .... or...
To get it even more accurate, put a 3k3 from lugs 3-2 and another 3k3 from lugs 2-1.
These additions will give you somewhere between a 2k - 2k5 pot
You should be able to "bias" a little easier now, unless your transistor is
VERY leaky ........ have you hfe checked them/bought a matched set ?
did you check your 20k trimmer also ?

In/Out ground connect to the "positive" ground of the whole circuit, just as if it was a "normal" ground - its just reversed in this case for the PNP
trannies.
( presume you are building one of the PNP versions and not Phillips NPN
"mindbender" version ? )

Regards,

Marty.