Topband: What are folks using for a T/R relay in the shack, to switch between beverage and xmit antennas?

Herb Schoenbohm herbs at
Thu Apr 21 10:17:44 PDT 2011

On 4/21/2011 10:08 AM, Mark Lunday wrote:
> I see some stuff out there from DX Engineering, but before I buy I wanted to
> check with others.  Thanks
> Mark Lunday
> _______________________________________________
Mark,  It is easy to build a switch with a 12vdc relay in a metal box 
using BNC connectors (saves drilling large hoes for PL-259's) and since 
in my case with the icom 746PRO there is not 12vdc available on the ACC 
sockets on TX, I did find 8vdc which is enough to drive a 2N2222A 
control Darlington type trigger. I use a large paddle mini switch for a 
means of cutting of the DC so the unit works straight through as  may be 
required at times.

  Another means of doing this is using the MFJ-1025 Noise Cancellation 
box (in sort of reverse mode) as an RF driven switch and bring the 
Beverage antenna(s) into the noise port connector.  No modification is 
required and you get a built in pre-amp if you need it.

Herb, KV4FZ

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