[BC] am receiver for monitoring at a 20 KW site...

[Burt I. Weiner]

Mike,

I had two SAGE receivers in the same room as a 5 KW transmitter with the hottest element of the array about 100 feet away.  The co-located transmitter was on 1300 kHz and I was trying to listen to KNX on 1070 and KFI on 640.  The Sage receivers are pretty bad and their eyes cross simply by mentioning the term, "RF" in their presence.

I built a two turn Faraday shielded loop about 1 foot or so in diameter made out of 8751 balanced audio wire.  It's important to make the loop as physically flat (symmetrical) as possible in order to get the best null.  I connected the two 8751 conductors in series and split the shield at the center of the loop, and tied the bottom ends of the loop's shield to the coax shield.  Rather than going for maximum signal of the desired stations, I went for minimum pickup of the 1300 kHz signal.  The loop was installed in the same room as the transmitter and even though it was not at maximum for the desired signals, the results were very good and I had no problem with reliable reception and no cross-talk from the local transmitter.

Burt