Marshall JTM30

This amp was on its third output transformer.  The stock OT is not of the highest quality, but I have to think that there was an underlying cause.

I replaced the OT, but also added some voltage spike protection features that should hopefully short out before the transformer does.  I also increased the value of the screen grid resistors, adjusted the bias voltage (the tubes are biased HOT in the stock circuit), replaced the flimsy output jacks, and rid the output stage of the strange switching circuits.

The crimp on connectors on the output transformer seemed a bit flimsy as well so I soldered those connections.  I also reflowed every solder joint on the PCBs.

I'm confident that these precautions will prevent another output transformer failure, but only time will tell.

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