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[AMPS] AL1500

To: <amps@contesting.com>
Subject: [AMPS] AL1500
From: kc5vdj@yahoo.com (Jim Bryant)
Date: Wed, 05 Dec 2001 19:02:03 -0600
2 wrote:

> Over-current fuses open to limit current, but over-current transistors 
> often short, which does not limit current.  The 8877 grid is capable of 
> dissipating 25w in AØ mode.  Since typical grid-cathode potential is c. 
> 57Vrms, 25w works out to c. 440 grid mA.  I have never seen a kaput 8877 
> grid that had uniform gold evaporation - such as would be the case with 
> too much DC grid current.   Mr, Murphy said that everything is more 
> complex than it first looks.


How much of this gold sputtering could be caused by long-term long-duration 
mild-to-moderate overdrive of the grid?

I ask this, because I know plenty of moron hams with amps that obviously do not 
understand the principles of the amplifier, and 
routinely overdrive them.  The number of Extra-Class hams who do so is 
astounding [thanks a lot, Gorden West]!

On a side note, as a no-code tech, I was having to explain basic antenna 
principles to extras who most obviously didn't know WTF 
they were talking about.

Basically, what I am asking is what is the factor of abuse in these 
gold-sputtering cases caused by what I call "ABCD Hams"?


jim
-- 
          ET has one helluva sense of humor!
     He's always anal-probing right-wing schizos!
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