DOCS:
http://www.madbeanpedals.com/projects/Dirtbaby/Dirtbaby2015.pdf
REV "0"
I have re-flowed suspect solder joints. (probably could find more)
Audio probed from input to IC1. Level drops to very low after R2 220k resistor.
It goes to IC1B and the schematic states pin 7 as input. No Audio there.
(see voltages below)
Voltages are all marked IC1 just checking that they are actually
IC1 IC2 IC3 IC4 left to right.
Chips 2 through 4 match doc voltages.
IC1 seems off...
Voltages for IC1 @ 9.3v regulated linear supply.
Docs Mine
1.6 6.3
2.93 4.1 to 5.3 varies
2.93 4.5 to 5.2 varies
0 0
4.24 4.3
4.26 556mv
4.24 7.5
8.4 8.89
Strange behavior: intermittent output appears as overloaded distortion. Like it's being pushed through a bad solder joint or component. Crunch Crunch with beat of music. Then nothing.
Changed out all the TL062 audio chips.
Turn Feedback up all the way and noise begins to run away.
Echo seems to be operating and speed control works.
Just no input passed through unless as mentioned above random bouts of distorted loud overdriven crunchy-ness..
Then nothing.
Bypass works
Any ideas are welcome!
http://www.madbeanpedals.com/projects/Dirtbaby/Dirtbaby2015.pdf
REV "0"
I have re-flowed suspect solder joints. (probably could find more)
Audio probed from input to IC1. Level drops to very low after R2 220k resistor.
It goes to IC1B and the schematic states pin 7 as input. No Audio there.
(see voltages below)
Voltages are all marked IC1 just checking that they are actually
IC1 IC2 IC3 IC4 left to right.
Chips 2 through 4 match doc voltages.
IC1 seems off...
Voltages for IC1 @ 9.3v regulated linear supply.
Docs Mine
1.6 6.3
2.93 4.1 to 5.3 varies
2.93 4.5 to 5.2 varies
0 0
4.24 4.3
4.26 556mv
4.24 7.5
8.4 8.89
Strange behavior: intermittent output appears as overloaded distortion. Like it's being pushed through a bad solder joint or component. Crunch Crunch with beat of music. Then nothing.
Changed out all the TL062 audio chips.
Turn Feedback up all the way and noise begins to run away.
Echo seems to be operating and speed control works.
Just no input passed through unless as mentioned above random bouts of distorted loud overdriven crunchy-ness..
Then nothing.
Bypass works
Any ideas are welcome!