Topband: Protecting an Array Solutions K9AY Loop from Transmitted RF

[N4ZR]

I'm in the process of building up a K9AY loop, using the Array Solutions 
boxes, and it occurred to me that I probably need to work out some way 
to protect the preamp in the shack-end box from transmitted RF, 
particularly since the K9AY loop is only about 60 feet from the vertical 
leg of my inverted L and I'll be running 1500 watts.

I can see maybe cutting off the DC to the preamp, but figure that won't 
be enough. Alternatively, I can probably work out a way to either open 
or short the feedline coming into the indoor box where the preamp is.  
Any advice as to which would be best (opening or shorting)?  I only have 
one spare transistor.

Advice much appreciated

-- 

73, Pete N4ZR
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