Topband: 4 Direction Reversible Beverages Remote Control via Coax Feedline

Les Kalmus w2lk at
Sat Apr 16 09:21:37 PDT 2011


Having done just that, here is what I did:

I have an Ameritron RCS-8V remote 5 port antenna switch at the support 
point for one of the Beverages.
The other beverage termination is connected to this switch through a run 
of direct burial RG-6.
Unused ports on this switch are not grounded.

In the shack I have a bias-T to inject a control voltage to reverse 
either beverage when needed.
One beverage controller is DX Engineering and one is homebrew and both 
have a bias T to handle the reversing relay voltage.

At the moment, I use the control box for the Ameritron to automatically 
switch beverage directions.
This is done with a diode matrix between the control box and the control 
lines going to the remote switch.
The positions of the control box switch are labeled NE, SE, SW, NW. The 
5th position is not currently used but will be used for another single 
wire beverage later this summer.
The matrix either does or does not inject the reverse control voltage 
depending on the position of the controller switch.
You need a diode in each control line to the remote switch plus another 
for each position that you want to inject the reversing voltage. This 
diode provides +12V to the relay on the bias T injector.
In my case, NE is forward to Eu and SW is reverse and requires the diode 
to inject the reversing voltage.
Each diode must point in the direction of the remote switch because the 
controller outputs +12V to the active position and must be rated for the 
relay current of 80-100ma and the control voltage with a safety margin.
If you want, I can supply the schematic of the system I use.

73, Les W2LK

On 4/15/2011 3:06 PM, k2waltk wrote:
> Hey all,
> I was wondering if anyone has built  a circuit to control the switching of a
> pair of two-wire reversible beverages, using only the coaxial feed to carry
> the control
> signals.  The usual design calls for 3 DPDT relays.  One relay is used for
> beverage selection and one each for direction and unused port termination.
> In other words, one relay for the NE/SW directions, another relay for the
> NW/SE directions and the third relay is used to select between the two
> reversible beverages.  The truth table is straight forward, but the
> circuitry to accomplish this is beyond this old, feeble brain addled with
> advanced CRS.  I can't figure out the circuitry (diode matrix?) to route the
> control signals to the 3 relays.  I understand how to isolate DC from RF,
> through the bias-T method and I've seen designs using positive, negative and
> AC to accomplish 'generic' remote antenna switching.  Maybe I can use a
> similar method to build the control switch back at the shack and the remote
> relay box.  Any of your suggestions, diagrams or references would be greatly
> appreciated.
>                                      73 de Walt - K2WK
>                                      Gordonsville, VA
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK

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