Help! MV52, PV8 schematics anyone?

Tubes Asylum

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Is this just a nasty coincidence or should I go back to solid state?
Dead component #1: A few months ago my second-hand Conrad Johnson PV8 (which was upgraded by Bill Thalman before I bought it) developed a low level hum which would not go away. All tubes checked out fine, hum was intermittent and not affected by any knobs, definitely isolated the problem to the PV8. Then a few days ago, it started frying fuses. I'd put a new one in and the minute I turned it on, the fuse would blow.
Dead component #2: I decided to try some new EL34s in my second-hand Conrad Johnson MV52 which started life as an MV50 and was upgraded by CJ. Tried Sovteks, Golden Dragons and Svetlanas. Was looking for more detail and dynamics, dealer recommended Electroharmonix. When I went to put them in, I noticed that one of the Svetlanas wouldn't bias so I tried the Sovteks which were fine. Turned all the bias screws to their minimum settings, put in the EHs, before I could do anything the tube in the same position started glowing extremely brightly, then started smoking, heard a crackle and pop from my speakers before i could shut it down and found the fuse for that channel was gone.
What's the deal???!!! Do I have bad tube karma? I bought them from different people about 9 months ago. Both components died within a few days of each other but my NAD separates are working fine plugged into the same outlet. At least I have a backup but I am extremely frustrated to say the least with my tube gear. there's a guy locally who can troubleshoot them but he needs schematics. I'd rather not have to send them from Tucson to the East Coast.
Any help or insights would be greatly appreciated.

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Topic - Help! MV52, PV8 schematics anyone? - desert dweller 19:24:15 09/01/03 (4)

Try CJ for the schematics - HKL 13:00:52 09/02/03 (1)

Thanks for your help - desert dweller 16:18:11 09/04/03 (0)

Re: Help! MV52, PV8 schematics anyone? - Barney's Beanery 03:43:50 09/02/03 (1)

Re: Help! MV52, PV8 schematics anyone? - desert dweller 07:08:14 09/02/03 (0)

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