Jim,
Firstly, I am not an expert on the Omni VI. But I wonder if the signal you are
hearing on the Omni VI frequency is not entirely what is being transmitted.
Even very weak signals can be strong on a receiver that is as physically close
as your 706 is.
Is it possible you are hearing a signal on the transmit frequency that you are
monitoring on the 706, but this signal is only a small part of what the Omni VI
is actually transmitting? In other words, the bulk of the transmitted energy of
the Omni VI is being transmitted on some other frequency as well as this lower
level signal on the indicated frequency.
A wattmeter just shows total energy transmitted, so a final amp that is
transmitting or oscillating at another frequency can show as lots of power
output on the wattmeter, but the signal on the "transmit frequency" is quite
low.
I would suggest the following test:
Connect the Omni VI to a dummy load. Set the power output to 10 to 20 watts,
something low that wont heat the finals too much. Send a continuous string of
dots. Tune the receiver in your 706 throughout its range of 30 kHz to 200 MHz
and note the frequencies where you hear the string of dots and the relative
strength of those signals. This might give some clues as to what is actually
being transmitted.
73, Darrell VE7IU
On Sun, 27 Apr 2014 14:01:02 -0500
Jim Allen <jim.allen@longhornband.net> wrote:
> Yes. I described this in the earlier post. When set to the exact same
> frequency, the Omni is heard by the 706 with a 700 hz tone. That doesn't
> vary with the sidetone setting which conflicts with what I read in the
> manual, or maybe I'm reading it wrong.
>
> 73 de W6OGC Jim Allen
>
>
> On Sun, Apr 27, 2014 at 1:48 PM, GARY HUBER <glhuber@msn.com> wrote:
>
> > Can you hear the Omni TX on the dummy load using the 706 in RX (no
> > antenna)? Or put the OMNI TX on the antenna and 706 RX on a dummy load..
> > Can you hear the OMNI VI?
> >
> > 73 & DX,
> > Gary - AB9M
> >
> > -----Original Message----- From: Jim Allen
> > Sent: Sunday, April 27, 2014 1:20 PM
> >
> > To: Discussion of Ten-Tec Equipment
> > Subject: Re: [TenTec] Omni VI mystery
> >
> > So far, it appears to be ok with WWV although USB and LSB are a few clicks
> > different.
> >
> > RIT/XIT both off, Split off, VFO on A, side tone set for 700 hz.
> >
> > I set the Omni to CW on 14.050.00 on a dummy load. I set the 706 with no
> > antenna at all on 14.050.000. Bring up power to a few watts on the Omni.
> > As I change the sidetone, but not the frequency in either radio, the signal
> > in the 706 does not change, indicating to me that the transmit frequency
> > isn't changing either, merely the sidetone. I thought the sidetone
> > indicated the transmitter offset, which would vary exactly with the
> > sidetone,
> >
> > Varying the sidetone throughout its range doesn't vary the received signal.
> >
> > I hooked up the antenna, and tuned in AD4ES, good strong signal on 14,032,
> > matched his tone to the sidetone at 700 hz, pushed the power to 100 watts,
> > and after his CQ sequence, gave him a call. Nothing! 4 or 5 times, I
> > repeated this. He stopped each time and began calling CQ again by the time
> > I sent my call. XIT/RIT off, PBT at 12 noon, VFO on A, Split off.
> >
> > I should be able to be heard at the station with a strong signal here.
> > Something is goofed up.
> >
> > 73 de W6OGC Jim Allen
> >
> >
> > On Sun, Apr 27, 2014 at 12:13 PM, Bob McGraw - K4TAX <RMcGraw@blomand.net
> > >wrote:
> >
> > Be sure XIT is not on nor is RIT on. It seems that the radio might not be
> >> receiving or transmitting on the same frequency. Also be sure you aren't
> >> in SPLIT mode.
> >>
> >> 73
> >> Bob, K4TAX
> >>
> >>
> >>
> >>
> >> ----- Original Message ----- From: "Jim Allen" <
> >> jim.allen@longhornband.net
> >> >
> >> To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
> >> Sent: Sunday, April 27, 2014 9:25 AM
> >>
> >> Subject: [TenTec] Omni VI mystery
> >>
> >>
> >> I have an Omni VI with Opt 3 installed, purchased from an SK estate about
> >>
> >>> a
> >>> year ago. After our move to Texas, I got an antenna up and got on the
> >>> air. The meter and a couple of other functions were inop so off it went
> >>> to
> >>> TenTec. They fixed all this, gave it a good checkout and got it back to
> >>> me
> >>> very promptly.
> >>>
> >>> I have the output going to a wattmeter, thence on to the AH-4 remote
> >>> tuner
> >>> which feeds the 130' dipole with twin lead. On CW, the transmitter loads
> >>> to 100 watts output, good SWRs etc.
> >>>
> >>> I have noticed an inability to get replies on CW. I spent an hour the
> >>> other night calling W1AW/5 in Missouri, another hour or so each this week
> >>> calling W1AW/1 and /2, and various other stations. Some of this I
> >>> attribute to being a 100 watt station with a wire antenna in a pile up.
> >>> There have been other instances where I have called and called only to
> >>> have
> >>> the other station start up a CQ again.
> >>>
> >>> Yesterday I decided to fire up my Icom 706 at QRP levels and work the
> >>> Florida QSO Party on 20M. To my astonishment, I had no trouble making
> >>> contacts with every station I heard, running 5 watts, other than being
> >>> treated as a weak signal (AGN?) which I'm sure was true. While doing
> >>> this,
> >>> I heard HB9CA in the Helvetia contest, gave him a call and after going
> >>> QRO,
> >>> made contact. I also worked W1AW/1 with 5 watts in 1 or 2 calls. I made
> >>> 25 or so contacts in Florida with the 706, all QRP.
> >>>
> >>> This started to puzzle me, so I shut down the 706 and fired up the Omni
> >>> VI. Once again, I had trouble getting responses. I tried fiddling with
> >>> the sidetone, thinking maybe I was not tuning to be inside the other
> >>> station's passband, but did not improve things. The "split" switch was
> >>> off!
> >>>
> >>> I am stumped to imagine why I can make contacts at 5 watts with the 706
> >>> but
> >>> not on the Omni VI at 100 watts, same antenna. The radio appears to be
> >>> operating normally in every respect. Is there something I am overlooking
> >>> in the set up of the Omni VI? Any other possibilities?
> >>>
> >>> TIA
> >>>
> >>> 73 de W6OGC Jim Allen
> >>> _______________________________________________
> >>> TenTec mailing list
> >>> TenTec@contesting.com
> >>> http://lists.contesting.com/mailman/listinfo/tentec
> >>>
> >>>
> >>>
> >> _______________________________________________
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> >>
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--
Darrell Bellerive VE7IU <ve7iu@runbox.com>
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