Re: Pye Black Box Restoration
Looking at earlier threads on this site, the first check must be to T1 whose failure is likely to be caused by C5. To check if the transformer is OK logic suggests that the resistance from the centre tap, shown where R16 is connected, should be the same to both anode connections viz pin 2 of the EL42 and the screen connection viz pin 5. That is, either side of the centre tap on the transformer. I don't have exact values but often this will be in hundreds of ohms not thousands with the anode resistance being higher.
Once confirmation that the output transformer is OK, change C5 & 6 before switching on. Conversion from microfarads quoted to nano farads etc can be found online but for C5/6 this is 5n and as said earlier, don't change everything just yet although unfortunately Hunts capacitors are bad news.
Hope this helps
Chris
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