Guitarpcb tonebender issues

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Post by aefpv »

I was making a Guitarpcb Pump'd up Tonebender, v4. I am able to get fuzz, but it is sputtery and at a lower volume. Below are my voltages for the IC and transistors. I am worried that I blew two transistors (Q1 and 2). My father, who is a EE, walked me through the process to test the transistors with a volt meter, comparing the resistance of the B to each C and E. I am confused how the pedal can potentially have two blown transistors and still work, creating fuzz (yet bad fuzz). Do these symptoms appear consistent with blow transistors or could the problem be elsewhere? Thanks for your time. -Andrew

Power supply: 8.85 V
IC 1: 8.66 2: 4.59 3: 0 4: -3.97 5: -8.51 6: 2.53 7: 1.43 8: 8.66

Q1 B: -0.01 C: -8.43 E: 0

Q2 B: -0.16 C: -8.43 E: 0

Q3 B: -5.04 C: -0.44 E: -0.32

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Post by Manfred »

Were the Q1 and Q2 blown out from the beginning, or did it happen during operation?

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