Hi,
I built a superfuzz using Mark Livesley´s stripboard layout.
But it only produces a moderate, dark overdrive and octave is not to be heard at all. The level is hardly above the bypass signal.
Have gone through with audio probe:
- If I measure the signal in the Expander-Pot, one hears aforesaid moderate distortion and the level is raised. I think, that means that Q1 and Q2 work correctly.
- measured in the Balance-Pot or in the Tone-Switch the sound is nearly identical, but the level clearly reduced. Whether the clipping diodes are soldered in or not, makes nearly no difference. Suppose mistake in the area around Q3, Q4, Q5.
-The level at the output connector is higher again, so Q6 should also function.
What gives to think to me, is the following: If I simply pull Q5 out of it´s socket, the signal gets much louder, more distorted and with a strong octave (it sounds broken and unstable, but closer to the typical superfuzz sound). Suppose, that Q4 and with it probably also Q3 also function, the mistake is to be searched in the area around Q5 .
However, I find absolutely nothing. I have checked the board several times for wrong connections, have cleaned it with acetone, have checked all component values, on suspicion have changed condensers in the doubtful area, have changed all transistors... The result stayed always the same
Measured voltages:
Battery voltage: 9.79 V
-------C-----B-----E--------
Q1: 5.63 0.71 0.14
Q2: 9.76 5.69 5.08
Q3: 7.46 2.79 2.31
Q4: 3.61 2.00 3.60
Q5: 3.60 4.35 3.59
Q6: 3.71 1.21 0.59
Particularly the big difference of the base voltages of Q4 and Q5 surprises me...
And I think the emitter voltages of Q4/5 should be lower
Can anybody help me??
regards, Immo
PS: I used an online-translator...
