[Elecraft] wire antennas

[Vic K2VCO]

wsm at amaonline.com wrote:

> Has anyone ever done any testing with multiple antennas on one
> feedline to see if they really do pick up extra noise?

Hm, nobody answered this. My feeling (and it's not based on experiments) 
is that it would normally not be a problem. For example, if you have an 
80 and 160 meter dipole on one feedline, then the unused antenna would 
be just as likely to pick up additional signals on the desired band as 
it would noise.  So while it might have a tiny bit more gain, the s/n 
ratio wouldn't change.

Having said that, the total signal and noise voltage delivered to the 
receiver front end would be greater, since the bandwidth of the 
combination of antennas would be wider. If the receiver's dynamic range 
characteristics were inadequate, there might be spurious signals 
generated in the receiver.

For example, if you lived in Europe where there are enormous SWBC 
signals around 40 meters at night, then you probably wouldn't want a 40 
meter dipole in parallel with your 80 meter one.
-- 
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco