I recently sold a Van Alstine Ultravalve Tube Amp to a buyer in a different state. I purchased it new in 2015 and took good care of it and used it pretty lightly. Before listing it I put in new EL34 tubes and a new GZ34 rectifier. I biased it and put it on my oscilloscope and it measured beautifully. Upon first trying the amp the buyer contacted me to say the the EL34 tubes were not lighting and wondered if I knew why. Then he told me that the rectifier tube had come apart. Finally he said that he put it a different set of tubes and the left channel wasn't working. I told him to send it back to me for a refund and I've just received the unit.
The base of the rectifier tube was indeed damaged and now there is only bare glass on the bottom. I put in a used JAN-CG-5U4G rectifier and all the working tubes that I had previously used before. I ran it on a dim bulb tester and guess what? It's drawing high current non-stop! It draws current even without a rectifier tube installed.
I have a hypothesis that I'd like to share and would like feedback. I'm guessing that the buyer accidentally put an EL34 in the rectifier socket and the rectifier in the EL34 socket. I'm wondering if doing that could cause the problems that I'm seeing now, and what the problem might be. Thoughts?
Many Thanks,
Jonathan
The base of the rectifier tube was indeed damaged and now there is only bare glass on the bottom. I put in a used JAN-CG-5U4G rectifier and all the working tubes that I had previously used before. I ran it on a dim bulb tester and guess what? It's drawing high current non-stop! It draws current even without a rectifier tube installed.
I have a hypothesis that I'd like to share and would like feedback. I'm guessing that the buyer accidentally put an EL34 in the rectifier socket and the rectifier in the EL34 socket. I'm wondering if doing that could cause the problems that I'm seeing now, and what the problem might be. Thoughts?
Many Thanks,
Jonathan
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