Marigold oscillation

[Blooze]

Populated the board and have it air wired to my prototyping pcb and transistors are all full lead length yet. Have the diode socketed and the zener alligator clip wired to try different ones. Lots of wire hanging everywhere, so that may be the problem. Using the following transistors with voltages:

Q1: 2N2222. HFe= 175: E 26.6mv,B 0.626V, C 4.38V
Q2: BC109C hFe = 510: E 42.3mv, B 0.641V, C 4.08V
Q3: MP38A hFe=64, leakage 140uA, E 0V, B 126mV, C 2.57V
D9J diode with 5.1V zener

I didn’t have any germs that are zero leakage and the 2N2222 is the lowest hFe silicon I have. I also only have the cheap gm328 tester.

If I have the effect volume and fuzz maxed and my guitar volume dimed I’m ok with any setting on the pedal. Whenever I roll the guitar volume back even a little it’s motorboat oscillation city unless I adjust the tone to the last third of the rotation and remove all bass. I can roll the fuzz back to 2/3 max and stop some of it as well which I expected. Even with the fuzz rolled back to 2/3 max or so I have to roll the tone to about 1/2 way to get it to stop. Lots of different combos.

Maybe this is just how a tone bender works as I’ve never played one, but any suggestions on what to explore I’d appreciate.

Hope this link works. This is me just moving the guitar volume knob.
Oscillation audio

 

[Blooze]

Never mind. I had another circuit breadboarded and forgot to disconnect the “out” jumper. Jeesh.

 

[Blooze]

Here’s what I ended up with. I only had MP38a transistors in NPN so I just keep trying combos of diode/zener with each one till I got decent voltages. Damn thing sustains for dayyyyyyyys.

 

[Flying]

I'm playing with the same circuit, these are the voltages I'm getting.

Supply Voltage = 9v
VCC = 8.34v

Q1: BC182A hFe = 220: E: 27.8mv, B: 0.631v, C: 4.17v
Q2: BC549C hFe = 581: E: 43.1mv, B: 0.648v, C: 4.01v

Q3: OC140 hFe = 76: E: 0v, B: 127mV, C: 2.418v
ICEO = 15uA to 20uA changes each time I test it!
ICEs = 8uA

D9E diode (it's all I have)
4v7 zener (4.6v at the zener diode cathode)

I’m wondering if I should up the zener to a 5v1 to get me closer to 2.5v on the collector of Q3?

I have two other OC140's, this first one is marked as a OC140 and CV7112

hFe = 70
ICEO = 11uA
ICEs = 5uA

And the other is marked only as a CV7112 but is a completely different beast!
hFe = 163
ICEO = 51uA
ICEs = 14uA