In response to Ed's comments ...
"
*Most of the AM-broadcast band interference reports we receive here in the
ARRL Lab are not coming from the transmitter. The most common cause of
interference from an AM broadcast station is an overloaded receiver.? There
are two ways to test this. The first method is to install either a
high-pass filter in line with the receive antenna input.? A bandpass filter
can also be used.? If the "harmonic" goes away, or significantly
attenuates, the harmonic is being generated within your own receiver.*"
His suggestions are rock solid. In my case, and since I live within several
miles of the majority of metro NYC AM station transmitters, I have a
commercial broadcast band filter (made by ICE) in the "loop" connection on
my Flex 6500. I can operate anywhere above or below the BCB and have no
problems. I've also tried the step attenuator. If I insert 10db of
attenuation, it drops the signal at 1940 down by 10 db, and by any
increment I use. All the NY stations are located in what is called the
"Meadowlands", 90% swamp - great ground conductivity. It's been rumored
that this is where Jimmy Hoffa is buried - no joke! If they have any ground
radials, they are likely in the swamp! I've also been able to hear this on
two other receivers, at two other nearby locations. Frank, W3LPL has
mentioned that its been heard several hundred miles away. Last night I sent
the station an e-mail, but so far, no response. I'm also going to watch
what happens at sundown. I do operate 160, but in the lower end, so for me
this isn't causing any problems - just following up for the group.
--
*Best 73 de WA2SQQElmwood Park, NJ"The only dumb questions are those we
don't ask"*
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