Topband: Comparing antennas

[Tom Rauch]

Bill, Pete, and others,

24dB is significant loss, and vertically polarized losses were near 
zero dB. That should be very easy to see, since it is a profound 
difference in level. Some SSB transmitters do not have that much 
difference in IM products and the desired signals!

>From an engineering standpoint, we really have no idea what-is-
causing-what when the references are vastly different, as when we 
compare a low dipole and a vertical. In a case where elevation 
patterns or power density with wave angles are grossly different, the 
water is muddied. It could be either wave angle or coupling loss we 
are seeing, we actually would have no idea what the root cause is.



In order to verify loss, we need two antennas with similar radiation 
angles and ERP, with only a polarization difference. Anything else  
would not tell us if it is a wave angle issue or a coupling loss 
issue we are dealing with.73, Tom W8JI
W8JI@contesting.com