[Amps] one mor SB-220 fix

[kingwood]

Gary,

        What you say about the RF choke reducing arcing is correct, but this 
is just one of its several functions.

         Your point about  C1 arcing is a valid point.  But, what if, as you 
say, it was set near minimum capacitance, and does not arc?  When my problem 
happened, I was operating on 20 meters.  I found no evidence of C1 arcing, 
just a fried (actually melted down) RF choke and an arced TR relay.  At any 
rate, the damage was substantial to the front end of my FT-1000D.

        The RF choke may be only rated at 125 Ma for continual use,  but 
what happens, instantaneously, during a "Big Bang?"  I have no way of 
measuring the peak current, but think it is safe to say that it would be 
several amps, often resulting in vaporizing the choke.  I see this quite 
often with the grid chokes. They are the same chokes as used across the 
output.  Of course, they are subjected to a very different current flow than 
the output choke, even in a "Big Bang."

 73 de Lon, K5JV

1110 Golden Bear Ln.
Kingwood, TX 77339

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