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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 (258.67 KiB) Viewed 4739 times
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- The_Twin2.jpg (248.91 KiB) Viewed 4739 times
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- The_Twin3.jpg (318.79 KiB) Viewed 4739 times
Re: Fender "The Twin" PCB issues
Posted: Sun Jun 28, 2026 8:45 pm
by laurie

- The_Twin4.jpg (298.88 KiB) Viewed 4738 times
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- The_Twin5.jpg (353.46 KiB) Viewed 4738 times
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- The_Twin6.jpg (173.54 KiB) Viewed 4738 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 (78.69 KiB) Viewed 4737 times
Re: Fender "The Twin" PCB issues
Posted: Sun Jun 28, 2026 9:56 pm
by Pepe
What an awful design!

Good luck with the rest of the story!