[NLRS] TRANSVERTERS

[Glen Overby]

Kris KC0REO wrote:
> Looking for help on interfacing transverters with a 756ProII. Looking to =
> get 432, 222, and 2 interfaced on this rig.=20

> I know I can order the transverters from downeast rig ready for this =
> radio but, I need help with rf/ptt switching.=20

> How can I switch the transverter tx/rcv, ptt/amp, and key  from one =
> transverter to another with little hassle? =20

One technique used by many rovers is a N-Way RF switch and piggyback PTT-High
over the coax with a simple inject circuit (I believe the proper name is a
bias T) consisting of a DC blocking capacitor between the radio and the line,
a 1uh (for 2M) inductor and a 1k resistor in series to a PTT-H source (I use
an op-amp and a FET).  Many of the DEMI transverters have everything needed to
do the reverse: a blocking cap and a PTT-H input.

My 2304 & 3456 transverters are set up for PTT-H over coax and PTT-L from the
back panel RCA plug.

Others have used PTT-L over the coax.  Using the 'idle' state RF to bring the
coax above ground potential.  This requires antenna switches to be insulated
so non-selected ports aren't shorted to ground.

I don't know for sure what the amp and key signals are.  I would expect an amp
to be daisy-chained from the transverter, possibly driven by the same PTT
signal?

Glen, KC0IYT