I have always used a 3 inch ferrite (TDK 9930) choke with for each
Beverage RG6 feedline (13 turns) near the shack entrance. There is a
common ground and on the remaining RG6 going to the radio (20 feet or
less) I have another 3 inch ferrite with another 13 turns of RG6. To
better describe they are for the RG6 a coil, a common ground, and
another coil. It has come to my attention by a seasoned topbander
that I have this all wrong and the decoupling coil should be close as
possible to the Beverage transformer. He reasoned that the long RG6
cable (some 500 feet long) couple random pickup right back into the
Beverage transformer and could also reduce the side lobe rejection from
the Beverage itself. So where is the best placement for for a feed-line
choke?
Please share with me your thoughts on this. Thanks
Herb Schoenbohm, KV4FZ
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