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Embarrassing Pro Jr problem...

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8/16/1999 4:13 PM

Embarrassing Pro Jr problem...

This may be difficult at a distance but here goes... I just sold one of my Pro Jrs over the web in order to raise some additional $$ for an upcoming bf Vibrololux purchase. It was in mint condition, running fine, with orig factory fender tubes (Sovteck EL84s and two Chinese Fender labelled 12AX7s). Just heard from the buyer who politely informed me that he is experiencing a major volume drop after the amp is running hot. As this was my first web sale, I feel more than slightly embarrassed about this and want to help him out to get the thing running properly. FWIW, it's a '95 PJ, the tubes were removed from the amp for shipping via UPS halfway across the continent, and I had to provide instructions for the buyer to reinstall the tubes (his 1st tube amp). Any ideas on the source of this problem?? Thanks!!

8/16/1999 4:29 PM
Benjamin Fargen	David, I know this sounds crazy.....but, did you confirm that the new owner replaced the tubes correctly?............four 9 pin sockets & four different tubes = endless possibilities for someone who is not familiar with tube amps. Benjamin

8/16/1999 5:20 PM
David P	Benjamen: Yep, gave him some VERY detailed instructions. The amp works just fine until it gets hot, then the volume drop-off occurs, so I expect things would not get that far if the tubes were not in their proper sockets.

8/16/1999 5:21 PM
David P	Oops, forgot to sign that last post!

8/16/1999 6:04 PM

Benjamin Fargen

David,

I'd say your best bet is to split the shipping cost and have him send it back so that you can get your hands on it and fix it. It is most likely something simple that you will be able to spot...cold solder joint, loose wire ect.

Did he try replacing the tubes with known good ones? Maybe they got knocked around a little during shipping. I know it's a long shot......but have him try all the simple stuff first! I am famous for turning something into a major job because I didn't check the simple things first!

Good luck and let us know what happens.

Benjamin

8/16/1999 5:39 PM
Les	This sounds suspicioously like a cold solder joint that got cracked open when it was shipped...

8/16/1999 6:01 PM
Gus	I fixed my pro jr that had this try problem. It turned out to be the ceramic cap(burned shorted) across the primary side of the output transformer there is a resistor in series(protection if the speaker is unplugged????)

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