[TenTec] Omni V.9 and RX-320 sub-receiver working fine

[Rick Denney]

Thanks to those who sent details for incorporating my RX-320 as a
sub-receiver for my Omni V.9.

The 320 is working happily running through a USB to RS-232 adaptor
from my station laptop, leaving the real com port for the Omni V. I
had to make a special cable for the V.9--Ten Tec implements lots of
strange and wonderful discrete controls on many of the pins of that
DB-25, and the serial cable really does just want to have the
conductors needed with nothing on the other pins. Using a 25-pin
cable, a null modem, and a converter to 9 pins caused the V.9 to start
sweeping down the frequencies.

As suggested in Carl's documentation for an older version of his N4PY
RX-320 control software that will also operate a Paragon II, Pegasus
or Omni V.9/VI, I used the V's auxiliary 12-volt output to feed the
coil of a small relay, with the ground side of the relay coil going to
the RLY (amp control relay) on the the V. Since I also use that for my
non-QSK amp, I made a box that connects the one phono plug to two,
pulling the ground through diodes to isolate them. The relay breaks
the contact to an audio plug when the V is transmitting, muting the
audio output of the RX320 during transmit. I have bought but have not
yet received a small headphone mixer so that the audio output of the
320 can be mixed with the headphone output of the V.

The arrangement also lets me control the frequency of the 320 using
the VFO knob on the V, as long as I don't mind that the V is also
changing frequency. The frequency, mode, and filter setting on the 320
can also be pushed to or pulled from the V with a single click.

The 320 gets its antenna from the receive antenna connector on the V,
which is already switched off during transmit.

It's a really slick setup, providing dual-receive capability and
essentially four VFO's. The memories in the 320 software can be used
as memories for the Omni V.9, too.

I'm surprised by how good the 320 receiver is. It's no match for the
V, but it's just fine for listening to a DX station during split
operation, so that the V's better selectivity and stronger front end
can be used to slice up the pileup. It's nearly as sensitive as the V,
and I couldn't find any signals with the V that I could not also hear
on the 320. The real filters on the V do make much nicer audio than
the digital filters on the 320, but that should be expected at the
relative price points.

Carl's software allows me to adjust the frequency display on the 320,
and I had to adjust it 640 Hz to match the V. (The V is pretty close,
so the 320 was off a bit, but consistently so on all bands that I've
checked.) The result is a well-integrated station, even if there are a
lot of wires piled up behind it.

I appreciate the information sent by several of you to get me
started--it allowed me to have everything I needed so I could mess
with it while the doctors have me under house arrest.

Rick, KR9D

---
Richard W. Denney, Jr. PE|Iteris, Inc.              |
Associate Vice President |107 Carpenter Dr. Ste 230 |    703.925.3819
rwd at iteris.com           |Sterling, VA 20164        |Fax 703.471.1757