HF Oscilation in "orange squeezer"

[Minion]

Hi, I just built a Orange squeezer Comppressor but I am have a LOT of BAD HF Oscilation.....as soon as the Tone I pluck starts to drop off the Oscilation gets really bad....I have built the curcuit exactly as shown accept I am useing a TL072 and am Running it off of a Bipolar +/-15v supply.....

But this Curcuit does work better than the many other curcuit I have tried on this Forum....Out of the 10 or so Pedals I have Built this is the only one that comes even close to working and I am far from an Inexperienced Builder......


any help.....Thanx

[Minion]

Another thing Neither of the 10k trim Pots seem to have any effect at all....I used the PCB Layout that comes with the Schematic.....


anyone???

[Minion]

Well....I tried Putting a 68pF cap in the feedback loop but that didn"t help so I then changed it back to run off of a Single supply at 15v and it got a Lot better but I can still hear it oscilateing (even in bypass).....

It seems to Oscilate in the Note of B ,and will start at about g and progressivly go higher in 1/2 note steps untill it get to B were it Badly feeds back and oscilates.....

Maybe this is the way it is supposed to sound??? It does have a Nice Crunchy distortion when it isn"t oscilateing......

I guess the last thing I try before scrapping yet another pedal is I will try putting a Resistor on the +15v supply to drop it down closer to 9v and see if that helps ,Maybe the Higher Voltage is screwing with the Bias of the Fets....

[slacker]

guess the last thing I try before scrapping yet another pedal is I will try putting a Resistor on the +15v supply to drop it down closer to 9v and see if that helps ,Maybe the Higher Voltage is screwing with the Bias of the Fets....

Probably a good idea, I wouldn't be surpised if trying to take this from 9volts to 30 would require some tweaking of component values.