Antenna switch question

[Bill Clarke]

Currently I physically change coax lines when switching the antenna from
one HF rig (K3) to the other HF rig (TS480). Of course it is fool proof
when it comes to making a transmit error. That said, I'd like to use a
coax switch for this purpose. Years ago I did this often, however, rigs
were less complex and sensitive back then - so I trusted simple coax
switches. I do not run rigs simultaneously on different antennas and
bands the operation is very simple.

Question is: What coax switches are recommended for this job and what db
isolation should I be looking for?

I do recall that in the USAF - all antenna switching at "listening
posts" was done with patch cords and panels. No switches. That was in
the days of the R390.

Thanks,

Bill W2BLC

--
Sent from my soup can with a tight string!
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[ve3dvy]

recently ther was a similar question in QST's Q&A   and they showed what
they had at W1AW.   rather than an antenna switch the have an antenna
patch bay.   so I created a similar setup.

your needs are simpler than mine but the basic Idea would work for you.
    I have some vintage rigs in addition to the main station so  I use
a  panel  that has several SO239 connectors,   each SO239 has a line
that goes to the antenna connection of each rig,  two SO239s in the case
of rigs with two antenna connectors like the K3.     Each SO239 is
labeled for its corresponding rig.    Then since I have 3 antennas   I
have 3 short coax leads with PL259s   each lead goes to and labeled for
each antenna.     so when I change antennas or rigs  all I do is connect
the lead from the antenna I want to use the SO239 corresponding to the
rig I want to connect it to.      there is no way to connect a rig to a
rig in error this way or more than one rig to one antenna.     It
essentially brings all the antenna connectors from the radios to one
panel and the same for the antenna leads.    the last thing is I have
three dummy SO239 connectors that are grounded one for each antenna.  
when an antenna is  not in use or when I am not operating the station  I
connect the antennas to the ground connectors for protection from static.

in your case all you need is one lead from your antenna and  an SO239
for each antenna connector on your rigs.  This is easily  expandable and
has excellent isolation that is probably better than any antenna
switch.    Just remember to use a metal box and to be sure its connected
to the station ground.    if you scrounge a bit you probably will find
that you can make this type of system for far less than buying an
antenna switch.



On 3/14/2012 5:00 PM, Bill wrote:

> Currently I physically change coax lines when switching the antenna from
> one HF rig (K3) to the other HF rig (TS480). Of course it is fool proof
> when it comes to making a transmit error. That said, I'd like to use a
> coax switch for this purpose. Years ago I did this often, however, rigs
> were less complex and sensitive back then - so I trusted simple coax
> switches. I do not run rigs simultaneously on different antennas and
> bands the operation is very simple.
>
> Question is: What coax switches are recommended for this job and what db
> isolation should I be looking for?
>
> I do recall that in the USAF - all antenna switching at "listening
> posts" was done with patch cords and panels. No switches. That was in
> the days of the R390.
>
> Thanks,
>
> Bill W2BLC
>

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Please help support this email list: http://www.qsl.net/donate.html