[Drake] L75; What went KERPOW??

[ed brooks]

May simply have been a momentary arc, with no lasting damage.  Recently 
I was on the air with my old Hunter Bandit, running about a KW out and 
things were well, when suddenly there was a loud "bang" and the amp shut 
down.  Later pulled it apart.  Blown fuse, no signs of problems.  
Interesting.  So I put it back together, replaced with fuse with a 
slightly lower value for testing,  and put it on the air.  Still perks 
fine at 1 KW, no problem.  I believe a dust trail shorted on the tuning 
cap so while I had it apart I cleaned the caps, but there was no other 
sign of damage.  I happened to be looking at the plate current meter 
just a second before the bang, and saw the current suddenly swing up.   
Mine had no odor, though, then or afterwards. 

Yes, we would like to hear what you find, and it is important you take a 
look, just as I did.

Ed, W5HTW

Dave Edwards wrote:

>Have not heard much from the Drake list lately...Anyway, wonder if anyone can suggest a likely culprit in the innards of my L75 amp?  I was having a chat on 20 CW. The amp suddenly made a beep sound (like a warning buzzer...what the heck could that have been??) and then a "ker Crack!" sound. 
>I hit the standby switch and finished the QSO without the amp. 
>Later, I turned the amp back on and it seems to be working fine. But, there is that yummy smell of burnt bakelite in the air. 
>So, when I get the chance I will pull it out of there and pop the lid to see what is going on. Can anyone suggest what could have gone south, and yet allow the amp to keep on working? 
>Just now it keys down at 320 mils and 2500 volts. The output about 650 watts.
>Any thoughts would be helpful. 
>If you are interested, I will post my findings here after I "dive in" !
>Thanks all;
>...Dave
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