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Re: I was going to pull the rectifier next - but the fuse blew

It's a pretty safe bet that the filter cap is at fault. The only reason why you should power up without the 5AR4 is to assure yourself that the power transformer hasn't been damaged in the last aborted power up. If the amp doesn't blow the fuse with the 5AR4 removed, then it's just the filter cap. You could do it yourself by taking a digital picture and drawing a diagram so you know where to reconnect all the wires and resistors, but it's a little daunting. Besides which, it's just the place where you don't want to make any mistakes. Although the amp runs at around 430VDC, on turn on with the modern voltage coming out of the wall, that cap could see voltages as high as 525VDC or higher. It would not be prudent to be guessing whether you are correct or not.

For what it's worth, your seller may not have misled you. Old filter caps do wear out. They are the weakest link in repowering old electronics. And the amp may have worked fine for the seller. It's just time for it to be done and when you do it, the amp should be okay for another 40 years.


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  • Re: I was going to pull the rectifier next - but the fuse blew - corerosin 13:46:45 03/14/07 (0)


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