SOLVED Woodpecker - no chop. Depth knob acts as reverse volume

Popnfreshbass

Well-known member
So my woodpecker build has been my first non functioning pedal. I get a signal in bypass mode, and when effect is engaged. But it’s just a dry signal. Level knob works as intended, depth knob is a volume knob but in reverse, and the switch and rate have no effect.

After some digging, transistors seem to be an issue with this pedal. I used a j201 for q1, a 2n5089 for q2, and a 2n6027 for q3.
the 201 is the smd adapter board from pedalpcb so no issue there. (Drain is reading 7.5v) although this is my first time using not the exact part. But after some reading it seemed like this was an ok sub for the pf5102.

The other 2 transistors were sourced from banzai music. My first time ordering from them. It looks like the 2n6027 may be a fake/ebay one as it matches the pics I’ve seen posted on here. I bought a few other odds n end from them(belton brick, tm011 transformer) should I be worried?

I have a basic understanding of electricity, but have no idea how to test if a transistor is fake or working as intended or if my meter could even do it… any help is appreciated.

 
if you only have a dry signal it could be multiple issues related to the part of the circuit that changes the amplification for the transistor to create the tremolo. Probably a good idea to look at the schematic in the build doc and check all of your part values and connections for everything that connects to the second leg of Q2. At the very least, it gives you something to do while waiting on a replacement Q3 to try, and you may get it working quicker too. Measure the voltage on pin 2 of Q2 and see if you notice any changes in it when the rate control is set at different places.

check your voltage on Q3, pins 2 and 3. share your measurements and post some pics of your build.
 
Ok got some proper readings tonight more and more convinced I have a fake 2n6027.

Fixed the Depth knob after I found a bridge between two resistors. So thats good. But still no chop, I basically have a boost pedal right now.

Q3-1= 6.8v with the rate pot @100% and 5v with it at 0%
Q3-2= 3.9v(rate pot does not effect)
Q3-3= 0.1v(rate pot does not effect)

Q2-1= 0V
Q2-2=1.2v
Q2-3=0v

I guess I’m a little confused on how and what R8 does. It is in parallel with 3 and 2 of Q3. This is the transistor that should be providing the tremolo effect correct?
 

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I am about to start this build and I too purchased a 2n6027 from Banzai. Guess I will find out if it works. Sorry, you had this trouble. I was really hoping Banzai would be a good solution for me here in Ireland.
 
I am about to start this build and I too purchased a 2n6027 from Banzai. Guess I will find out if it works. Sorry, you had this trouble. I was really hoping Banzai would be a good solution for me here in Ireland.
Ya I knew it was too good to be true. They had all the oddball parts I needed that I couldn’t get from Tayda in one place. I will say that there Belton brick works great in the reverb and the tm011 transformer worked in the bit commander. But I got hosed on the v3207, and the 2n6027 was a dud.
 
Ya I knew it was too good to be true. They had all the oddball parts I needed that I couldn’t get from Tayda in one place. I will say that there Belton brick works great in the reverb and the tm011 transformer worked in the bit commander. But I got hosed on the v3207, and the 2n6027 was a dud.
I bet they don’t test their batches of stuff and chance that it’s genuine.
 
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