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[Amps] Big bang

To: <amps@contesting.com>
Subject: [Amps] Big bang
From: 2@vc.net (Rich)
Date: Fri, 8 Nov 2002 16:54:02 -0800
>TL922A
>It had been on the shelf for couple years.
>Two days ago brought it out, cooked it for several hours and had used it on
>160 ssb during
>evening.
>Day before deer season opens so was not surprised to hear a rifle shot.
>Then realized it was dark outside.
>Through vents near the filament transformer I could see a small flame.
>Roasted one marshmallow, then made two contacts with an Indian reservation
>in Oklahoma.
>Smoke signals got weak so decided to look inside.
>Found bits and pieces of  C3, 33uf , 160v. Used to be wired across 0.    80.
>of  T2.
>Cause, Pick one:
>1. died of old age
>2. victim of major disaster down  wind
>3. operator malfeasance
>
**  4.  None of the above. 
-   Why?  The  HV bypass C - 2000pF - is only about half of what is 
needed to protect C3 from RF on 160m.  Fix:  Replace C3 and add C in 
parallel with the 2000pF.  
-  An article on circuit improvements for the 922 is available on my Web 
site.

>Solution;
>1. junk the amp
>2. replace the cap
>3. admit I'm an Arkansas  chicken farmer, not a technician, and get help
>
>Should never have offered the L7 some down time,

cheers, Doug

-  Rich..., 805.386.3734, www.vcnet.com/measures.  


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