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Old January 29th 09, 04:06 PM posted to rec.radio.amateur.antenna
Jerry[_5_] Jerry[_5_] is offline
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First recorded activity by RadioBanter: Jun 2008
Posts: 133
Default Antenna Replacement Experiment


Hi Spin

There may be different rules for connecting external antennas depending on
if the objective is to get max gain or to get strongest null response.
An external, capacitor tuned loop is a high Q device and appreciates loose
coupling when used to receive weak signals.
If the objective of the loop is to null out a specific frequency, I
suspect the direct connection of the external loop will result in very
effective nulling.
I hope you try this antenna modification and report the results

Jerry KD6JDJ



"Spin" wrote in message
...
Jerry;

I know how to couple an external loop to the internal ferrite antenna of
the radio. I believe that i would get better nulls & gain by removing the
internal antenna & directly connecting a box loop in it's place. Please
correct me if i am in error.

"Jerry" wrote in message
news

"Spin" wrote in message
...
Is it feasable to remove the ferrite antenna from an am radio & replace
it with an external multi-turn box loop with the same primary/secondary
inductance?



Hi Spin

I cant offer any information about removing the ferrite antenna and
replacing it with an external loop. But, I can tell you that a few
turns of wire from the loop, wrapped aroung the radio, with the original
ferrite antenna connected as normal, can be made to couple the external
loop to the receiver to greatly improve reception.

Jerry