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