[TowerTalk] Circularly Polarized Receive Antenna

[Brian Beezley]

On 8/13/2025 9:37 AM, Steve Jones wrote:
> Brian,
> How about one vertical antenna on one RX and one horizontal antenna on a 2nd
> RX, with the two signals combined in diversity mode?  My K3 can do that.
> 73,
> Steve
> N6SJ

Steve, your comments are right on. After I sent my message, I was 
thinking that maybe I should add something about using two antennas as 
an alternative. I'm not familiar with the K3, but I know that several 
current transceivers have two coherent receivers. You can either listen 
to two signals, one in each ear, or combine them to maximize S/N, either 
manually or automatically. The antennas don't have to be perfectly 
orthogonal. Their polarization sensitivity just needs to be somewhat 
different for automatic S/N maximization to work. You might even benefit 
from location diversity if the antennas are far enough apart. The 
distance needed may be a bit large on 160 though. What I like most about 
using two antennas is that you aren't stuck with a suboptimal axial 
ratio if you can't accurately determine your local ground constants. 
Adjusting the combination to maximize S/N implicitly accounts for 
whatever ground constants you happen to have. It also accounts for the 
incoming elevation angle. I would use an automatic algorithm if possible.

Incidentally, I mistakenly sent my message to TowerTalk. I meant to send 
it to TopBand. I later sent a copy there, but it hasn't shown up yet.

Brian