[TowerTalk] crosstalk between beams on a common boom (such as c31xr)

[David Hachadorian]

----- Original Message ----- 
From: "Al Williams" <alwilliams at olywa.net>
To: <towertalk at contesting.com>
Sent: Friday, March 18, 2005 10:11 PM
Subject: [TowerTalk] crosstalk between beams on a common boom 
(such as c31xr)


> For example, transmitting on a 20 meter beam while listening on 
> a 15 meter beam.
>
> How great is the risk of damaging the front end of a receiver 
> listening on one beam while transmitting on a second beam
> when both are close spaced?

How far apart are those elements on the multi-feed C31XR, just a 
couple of feet? If you don't do everything just right, you will 
blow the Rx every time. I would suggest dedicated sets of stubs 
on the three feedlines, in addition to the BPF's. That's what 
Natan, formerly of Force 12, recommended when I talked with him 
about this subject. There is a 5B4 doing this with a C31XR, and I 
remember him writing about it. It took a fair amount of work for 
him to get overload under control, but he is doing it 
successfully, at high power.


Dave Hachadorian, K6LL
Yuma, AZ