Hi Peter,
Great answer! I never thought about broadband IMD generating hash in a
receiver front end. That doesn't seem to be a problem with my 751A's.
I wondered the same thing myself, why so many people put what should be a
very poor receiving antenna up and notice improvements.
I always considered it to be because a poor antenna, just like an
attenuator, backs the receiver down into a non-linear range of the AGC
system, where background noise isn't "brought up" through gaps in the
desired signals. The IMD thing is certainly another possibility with todays
wide front ends.
> At 20:47 8/10/1998 +0200, Giulio IK2DED wrote:
> >
> >Then I have put a ... low dipole about 1.5 meters up. Incredible,
> >the noise was absolutely less than 1 on my S meter, the S/N was
> >really much more better than my vertical system.
Giulio might also have local noise, propagated by ground wave. If the noise
is ground wave propagated, a low horizontal antenna could offer better S/N
ratio than a vertical.
73 Tom
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