Home Forums GuitarPCB Build Support Boogie 57 – First Kit Build (solved) Reply To: Boogie 57 – First Kit Build (solved)


We have success!!!!

What we learned today is the audio probe method is the best manner of troubleshooting.

I got the parts today to build a new audio probe, which I did.

The first test was the drain of Q1…. sounds find.  Q2 drain sounded horrible.  In fact, it sounded like the horrible output I was getting.  So I adjusted the trim pot of Q2 until the audio probe output sounded like I thought it should.  Too low or too high got no sound, but I was able to find the sweet spot on the trim pot.  I then followed around to Q3 and Q4 and did the same thing.  Once I had adjusted all of the trip pots to where things sounded like I was expecting, I plugged into the amp and the pedal sounded great!!  Just like it should.

Here are the NEW voltages that actually made the pedal sound correct.

Q1: 5.01
Q2: 4.2
Q3: 3.9
Q4: 4.9
Q5: 8.9

What I learned is that even though the instructions say put all Q voltages at a certain number, the audio probe helped fine-tune the true numbers.

So now I am going to work on putting the unit in the enclosure and seeing if everything continues to operate.

Thanks to all who contributed suggestions on what to look at.  Now I know what to look for if my second build has a problem!