Re: In praise of the Ultra FM950
I have one of these. Initially I changed just the larger Hunts caps and it worked fine for about 3 years. Slowly performance dropped off and was restored by changing the final small value ~1n Hunts caps. It just goes to show that Hunts caps can deteriorate in front of your eyes!
Interestingly the grid capacitor on the output valve is a disc ceramic, suggesting that even back in the day Ultra knew Hunts paper type were inclined to be leaky.
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