SOLVED Busted TS9 - Troubleshooting

[EGRENIER]

Dear experts,

I got my hand on a busted TS9, and offered a friend to troubleshoot the issue. Long story short, he inserted a 12v reverse polarity adaptor, saw or smelled the smoke and voila.

Remotely, we had identified that the reverse polarity/voltage regulator diode had broken in half, D8 in the following diagram.


My friend replace it with a 1N5819, I know that it’s not the same as a W30C, and will not act as voltage regulator, but that should not impact the circuit.

A few picture of what I’m working with followed my my actions.






Through visual inspection I noticed that the 100u (C17) cap was blown and for good measure also replaced the 47u (C16) cap.


I also notices some white residue between a cap and a resistor:



So I replaced the cap, but not the resistor…


Current state:
- works in bypass
- Switch works, I see a very faint red in the LED, reading a voltage of only 1.78V. I tested the LED at 9V and it shine bright.
- IC readings with the switch on:
1: 0.8v
2: 0.77v
3: 3.34v
4: 0v
5: 1.03v
6: 0.93v
7: 0.92v
8: 9.06v

- When engaged, the pedal only produce white noise that seem affected by the Level and Drive pots.

So now I can’t see anything suspicious visually to replace and not knowing the board, find it hard to audio probe.

Any suggestions ?

 

[giovanni]

Thanks to all who posted on this feed. I am trying to fix an elderly and busted TS9 - this feed has been very useful. There are a few problems with this TS9 including no signal output at the moment. I am working through issues. Does anyone have any idea why the LED remains on all the time? The momentary footswitch appears to be working ok in that continuity across the switch is present when the foot switch is pressed. With battery connected and input jack inserted LED remains on, and the footswitch operation has no effect on this state. Any suggestion sappreciated

Maybe you can start a new thread and post pictures of the board etc?

 

[EGRENIER]

Thanks to all who posted on this feed. I am trying to fix an elderly and busted TS9 - this feed has been very useful. There are a few problems with this TS9 including no signal output at the moment. I am working through issues. Does anyone have any idea why the LED remains on all the time? The momentary footswitch appears to be working ok in that continuity across the switch is present when the foot switch is pressed. With battery connected and input jack inserted LED remains on, and the footswitch operation has no effect on this state. Any suggestion sappreciated

Yep, I’m with @giovanni on this… start a new thread, put pictures, voltage readings, etc. This thread is marked solved, so it won’t get the attention you seek.

Good luck…

 

[woollybaabaa]

Maybe you can start a new thread and post pictures of the board etc?

OK will do. Many thanks

 

[woollybaabaa]

Yep, I’m with @giovanni on this… start a new thread, put pictures, voltage readings, etc. This thread is marked solved, so it won’t get the attention you seek.

Good luck…

OK cheers. will do.