Need help to debug Guvnor...

Forum dedicated to helping people debug and troubleshoot non-functional pedals or builds. Please use an clear and informative title, indicating circuit and basic problem. Don't forget to mark the issue as fixed if this is the case.
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bluesfaker
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Joined: 24 Jan 2010, 03:05

Post by bluesfaker »

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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DrNomis
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Post by DrNomis »

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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