Topband: Harmonics - filtered

George & Marijke Guerin gmguerin at
Wed Jul 2 09:34:25 EDT 2003

I agree with Mike, W4EF

Here, I have tested my beverages and a pair of pennants with and without
high-pass filters, and I find lots of junk dissappears when a high-pass
filter is between the RX antenna and the radio.  The best location seems to
be just before the preamplifier.  The tuned circuits in the KD9SV style
pre-amps help reduce harmonic distortion as well.

BTW, I find more coupling of BC band hash on a beverage 25 degrees off a
local station than on a phased pair of pennants aimed almost directly thru
an AM 930 station about 1/2 mile away.  I guess it is because of the amount
of wire available for coupling to the AM signal, i.e., 500+ feet of beverage
wire and some reradiation thru neighbors electronic appliances, vs 148 feet
of wire on the pair of pennants with better spacing to the nearest neighbor.

73    George    K8GG

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