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Fender "The Twin" PCB issues

Posted: Sun Jun 28, 2026 8:44 pm
by laurie
Early Fender PCB amps *always* have heat related issues. Always.

This is the Red Knob "The Twin" that I'm currently reconditioning.
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The_Twin1.jpg
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The_Twin2.jpg
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The_Twin3.jpg
The_Twin3.jpg (318.79 KiB) Viewed 788 times

Re: Fender "The Twin" PCB issues

Posted: Sun Jun 28, 2026 8:45 pm
by laurie
The_Twin4.jpg
The_Twin4.jpg (298.88 KiB) Viewed 787 times
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The_Twin5.jpg
The_Twin5.jpg (353.46 KiB) Viewed 787 times
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The_Twin6.jpg
The_Twin6.jpg (173.54 KiB) Viewed 787 times

Re: Fender "The Twin" PCB issues

Posted: Sun Jun 28, 2026 8:57 pm
by laurie
The original 10W board mounted resistor arrangement could never (ever) have been OK. There is simply too much heat for that arrangement. The replacement resistors are specifically for high power dissipation and they mount to a heatsink. This is the correct engineering for this circuit.
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25W.png
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Re: Fender "The Twin" PCB issues

Posted: Sun Jun 28, 2026 9:56 pm
by Pepe
What an awful design! :shock: Good luck with the rest of the story!