[AMPS] Can't get rid of the boom,boom,boom...

measures 2@vc.net
Sun, 5 Mar 2000 14:20:10 -0700


>
>Gents:
>
>Having watched the fur fly for several months on the subject of parasitics
>and the like....it reminded me of an old tune.."You can't get rid of the
>boom, boom, boom...no matter what ya do."  Or can you?
>
>I have a TL-922, one day it went boom when I was using it.  The band switch
>vaporized...yes vaporized.  People told me I must have done it due to poor
>op practices.  So, $80 bux later..I installed the new band switch.
>
>About 2 months later, boom....a tube shorted and blew several diodes and
>other parts.   Puzzled, I spent several hundred dollars for new bottles and
>did all the "measures" mods including installng the vacuum relay mod.
>
>The amp purred like a kitten cept some internal arcing on one of the PS
>caps.  Like a LID, I ran the amp several months on the side hoping to find
>the arcing (originally thought it was a "seeable" arc.)  Well, you figured
>it out, I sagged one of the tubes and took out a couple of 10 cent parts and
>the tube.
>
>That mistake was mine.
>
>But the point is, what ever the boom,boom, boom was..it hasn't returned.
>Many can postulate as to what I was doing wrong or what stars were in line
>with what planets..but as far as I can see, the mods that I did took care of
>the problems I originally experienced.  The best $20 bux I ever spend.
>
>If anyone has experienced similar probs with their TL-922 and have spent in
>excess of $400 bux in parts....try spending the 20buxs and try the
>"measures" mods.  If you don't want to buy the parts from him, go elsewhere
>and try it.  I would be interested in your results.
>
Thanks for the thumbs-up, Jerry.  Be sure to say hello to Aunt Minnie for 
me if you are going to attend her 90th birthday party on 1 April.  .  

A word of caution on Harbach suppressors.  If the suppressor for a 922 is 
short on L - the VHF Q of the suppressor may not be low enough to prevent 
intermittent oscillation at c. 120MHz.  .  A VHF suppressor that runs 
cool at 28MHz is unlikely to be very lossy at VHF.  
>
cheers

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