Author Topic: NPN boost troubleshooting  (Read 2844 times)


NPN boost troubleshooting
« on: September 19, 2006, 01:39:07 PM »
Hi everyone,
I have some problems that others have noted with this project:
I only have effect on when my volume on the guitar is at 10. The effect was very
loose/farty etc. I had to hit the strings quite hard as well.
I realized I had an audio taper pot. After replacing this with a 5k linear, the sound cleared up,
and I no longer had to hammer on the strings, but...I still need the volume on 10 to hear anything.

Here are the readings from the transistor, metal can 2222 type.
Collector: 8.21
Base 0.35
Emitter 0.35

I presume that something is the matter here...any ideas? I measured from the ground
on the stereo jack and from the board...


Re: NPN boost troubleshooting
« Reply #1 on: September 19, 2006, 03:33:40 PM »
The base should not be the same voltage as the emitter. You have a wiring problem around the base and emitter.