[TowerTalk] Remote switch

[jimlux]

On 10/23/19 8:32 PM, Kim Elmore wrote:
> I’m a bit puzzled by the need for lots of isolation in such a switch. I understand why it’s needed between different transceivers, but how much is truly needed between antennas to the *same* transceiver? How much isolation exists between the antennas themselves, regardless of the switch? As an example, how much isolation is there between my 20 m tribander and my dipole for 17 m, all on the same mast? It’s got to be much less that across the ports of the RCS-4, doesn’t it?
> 

An interesting question - I think it really depends on "how deep do you 
want the nulls/sidelobes to be" - if you have an antenna with -20 dB 
nulls, and you have a dipole connected with a switch with 10 dB 
isolation, then your nulls are limited to -10 dB


People also use these kinds of switches to switch band select filters in 
multi op kinds of stations (Field Day?) and switch isolation is pretty 
important there.