Topband: AM interference on 1840,

Peter Bertini radioconnection at
Mon May 20 15:22:57 EDT 2019

If the problem is related to receiver overload, than a trap at the BCB's
operating frequency will correct the problem.  Unless the problem is
related to a non-linear junction (rusty fence wire, etc.) generating local
IMD or harmonically related signals due to rectification.

If the problem is the actual presence of a harmonic radiating from the BCB
transmitter, than no amount of filtering at the ham's location will cure
the problem.  Using a receive filter on 1860 will attenuate both the
harmonic signal and desired amateur signals.

There can be advantages to having a high pass filter that limits BCB signal
levels, but it will not cure this problem.

The traps belong  at BCB transmitter site if it is a real harmonic..

If I had this problem I would explore using a noise cancelling system (MFJ
or one of the Russian eBay
kits) to try and null the direction the signal is coming

Pete W1BR

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