Need help to debug Guvnor...

Frequent questions about dead or faulty pedals. Whether you repair, mod or build pedals, debugging is important. Threads about general debugging problems irrespective of the circuit involved...

Need help to debug Guvnor...

Postby bluesfaker » 12 Feb 2010, 21:59

Having searched for this many times, and not just all over this forum, I think I have an undocumented problem. :cry:

1) I am getting around 9v on all IC pins, dropping to 8.5 V on pins 2,3,6,7, using both a TL072CP and an LM1458.
2)When I use a power supply (standard boss thing, 9V, 200 ma), the pedal functions differently in a number of ways.
3) I am getting no sound in either bypassed or non bypassed settings, but a faint hum when using a power supply even though I am getting 9V on the board output and input.

I am completely flummoxed, have no idea how to troubleshoot past what I've done, and have verified the switch is working perfectly.
I would greatly appreciate any help with this. :scratch:
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Re: Need help to debug Guvnor...

Postby DrNomis » 13 Oct 2010, 13:28

The only IC pin that should have about 9Volts on it,should only be pin 8,here's a list of what should be on each IC pin:

Pin 1,4.5V
Pin 2,4.5V
Pin 3,4.5V
Pin 4,0V (Connected to circuit Ground)
Pin 5,4.5V
Pin 6,4.5V
Pin 7,4.5V
Pin 8,9.0V (Or thereabouts).

Hope that is of some help.... :)

The voltages you are getting indicate to me that something is shorting out somewhere,or the IC has had it.... :)
Genius is not all about 99% perspiration, and 1% inspiration - sometimes the solution is staring you right in the face.-Frequencycentral.
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