TS808 troubleshooting

I

Itsmedant

Active member
A coworker gave me his TS808 to trouble shoot for him and I’m not 100% sure where I should start.

At first he said it was making a lot of weird noise whenever he was about to turn it on or if there was any movement around it, he reflowed the jacks and now there is no sound at all.

I’m thinking it’s a bad switch but not 100% sure yet, just got it taken apart right now
 

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I would start by plugging it in and trying it out.

I would then inspect all the components visually, including the solder joints on the jacks. Pay attention to the condition of any electrolytic caps and doublecheck any protection diode.

I would check voltages at pins 3 and 8 of the IC and at collector and base of the buffer Qs.

If all of that checks out and there’s still no sound, I’d audio probe.

I would probably avoid the footswitch until completing all the above (which really doesn’t take that long) because if it IS the footswitch, then you have other issues like sourcing a replacement.
 
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An Ibanez TS808 (versus a clone) has a momentary switch which was known to wear out (about a 1" square stomp switch vs. the rectangular one on a TS-9) and employes a FET & transistor-based flip-flop buffered bypass circuit.
Try a little Deoxit being applied from the 'stomp' side in the cracks, aiming for the proverbial center. This will drip down into the contact area. Let it sit for a minute then actuate the switch to work it out. Then follow up with a little more Deoxit as a rinse. Let dry for 10 minutes.
If that did not help, check the switching FETs (Q2 & Q4 on the TS-9 schematic) by hard-wire jumpering (small alligator clip terminations) the Drain and Source of the FET that is currently engaged according to the LED indicator. Q2 is engaged when the LED is lit and Q4 when the LED is off.
 
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