TenTec
[Top] [All Lists]

[TenTec] Omni VI Plus freq. readout

To: <tentec@contesting.com>
Subject: [TenTec] Omni VI Plus freq. readout
From: scott@wowpage.com (Scott Johnson)
Date: Thu, 3 Oct 2002 15:27:17 -0400
I have to chuckle over all this.  My first radio was a Ten-Tec Century 21,
and it didn't even HAVE a digital frequency readout.  I seem to recall
having no trouble using it, regardless.

Is this really worth bickering for days over?  It's sure affecting the
signal to noise ratio on this list.

I have two radios that have nice, accurate frequency readouts, an IC-756PRO
and a Jupiter.  I have one that doesn't, a Scout.  I would have to bicker
with myself, and nobody wants to listen to that. :)

     Scott

--
Scott Johnson (scott@wowpage.com) (s.johnson@klotzdigital.com)
ICQ: 30730876 ICBM: N33 45 50.6 W84 49 31.3 (+- 3dB)

> -----Original Message-----
> From: tentec-admin@contesting.com [mailto:tentec-admin@contesting.com]On
> Behalf Of n4lq@iglou.com
> Sent: Thursday, October 03, 2002 11:32 AM
> To: Robert & Linda McGraw K4TAX; David Hammond; tentec reflector
> Subject: Re: [TenTec] Omni VI Plus freq. readout
>
>
> 1. My TS-930 was designed in 1987 or so and it's readout is far more
> accurate than any Omni.
>
> 2. Design technology (as far as frequency accuracy) was quiet adequate in
> 1987. TenTec chose to continue manufacturing radios based on 1975
> technology.
>
> 3. Using a tuning knob is not the issue here.
>
> All I can say is "get over it". The old Omni 6+'s readout is not accurate
> by standards over 15 years old. If you can live with it then fine but
> don't bother trying to convince us that it is of no significance.
>
> Another thing we all need to keep in mind. Although a lot of us,
> including me, like TenTec radios, this mail reflector is for DISCUSSION
> about TenTec radios regardless we like them or not. Complaints, gripes,
> negative comments are just as welcome as compliments. The only
> requirement is that the TOPIC be TenTec. This is not the First Church of
> TenTec. Owners, non owners and spectators are all welcome here.
>
> -----Original Message-----
> From: Robert & Linda McGraw K4TAX <RMcGraw@Blomand.Net>
> To: David Hammond <dhhdeh@concentric.net>, tentec reflector
> <tentec@contesting.com>
To: <tentec@contesting.com>
> Date: Wed, 02 Oct 2002 21:22:18 -0500
> Subject: Re: [TenTec] Omni VI Plus freq. readout
>
> > Three questions:
> >
> > 1.  When was the Onmi designed and when was the IC 756 Pro II designed?
> > 2.  Do you think time base and design technology stood still during
> > this
> > period?
> > 3.  Does the tuning knob on your radio work and do you know how to
> > correctly
> > use it?
> >
> > >From the Tentec Omni VI+ manual:
> > FREQUENCY ACCURACY    +/- 50 Hz @ 25 degrees C. (NOTE: the frequency
> > will
> > shift noticeably for  1 - 2 minutes while the oven heats up when first
> > turned on.  Leave DC power connected to the rear panel el eliminate
> > this
> > turn-on drift).
> >
> > And I see all the P'n and Moanin' over 10 Hz.
> >
> > I use my Omni VI+ on 20M PSK31 and yes I see many signals in the 500 Hz
> > passband.  Never have a problem finding my schedule or frequency.
> > Guess my
> > tuning knob works and I know how to use it.
> >
> >
> > 73
> > Bob, K4TAX
> >
> > ----- Original Message -----
> > From: "David Hammond" <dhhdeh@concentric.net>
> > To: "tentec reflector" <tentec@contesting.com>
> > Sent: Wednesday, October 02, 2002 8:58 PM
> > Subject: [TenTec] Omni VI Plus freq. readout
> >
> >
> > > Hi Everyone,
> > >
> > > Once again I am compelled to comment on this thread having spent a
> > lot of
> > > time seeking to improve this very specific Omni VI problem. It's real
> > and
> > it
> > > does exist.
> > >
> > > After 5 1/2 years of Omni VI ownership (prior to selling it this past
> > > Spring), I chased improved frequency readout accuracy on this radio
> > and
> > came
> > > up with the following conclusions. My Omni VI suffered from both
> > frequency
> > > repeatability and accuracy problems considerably greater than other
> > > transceivers I have owned. In fairness to Ten Tec though,  the Omni
> > VI
> > and
> > > VI+ were never spec'ed to super-precise frequency accuracy.
> > Nevertheless
> > > this problem bugged the heck out of me over time. So I embarked on a
> > series
> > > of modifications seeking an improvement.  Funny, I  thought that
> > > experimentation was in the true spirit of ham radio from days gone
> > by.
> > > Anyway......
> > >
> > > The frequency repeatability problem was vastly improved if not solved
> > > outright by substituting the 2ppm TCXO for the original crystal oven
> > in
> > the
> > > reference oscillator. A tremendous modification for older Omni VI's.
> > About
> > > $40 and hours work.  As I have said before, it is the best change Ten
> > Tec
> > > has come up with for the Omni VI and VI+.  While many crystals do
> > exist in
> > > the radio's L/O circuit, unlike in the Omni V, the VI's L/O crystals
> > are
> > > tied to the reference oscillator and cannot be individually trimmed
> > per
> > se,
> > > for improved frequency accuracy. Small deviations do exist from band
> > to
> > band
> > > but are not a real bother IMO.
> > >
> > > Th real culprits in the Omni VI are the BFO crystals located on the
> > board
> > > directly under the in-board speaker. This circuit is subject to
> > significant
> > > thermal drift coming and going in response to rig-generated heat and
> > even
> > > changes in ambient room or Wx temperature. Attempting to fix this
> > problem
> > I
> > > first removed the speaker to allow for convective cooling up through
> > the
> > > speaker grill.  Good but not great results.  Then I substituted
> > higher
> > > quality ceramic trimmers for the USB and LSB trimmers. No real
> > improvement.
> > > Finally I ordered custom built USB and LSB BFO crystals from ICM in
> > > Oklahoma. About $70 and an hour's work later, I  had them installed.
> > This
> > > change removed about 99.5% of the thermal drift resulting in better
> > than
> > > spec'ed display accuracy.  The BFO circuit is the culprit in this rig
> > > causing the problem with frequency accuracy. It is noticeable in SSB
> > over
> > > periods of extended TX activity. New custom crystals and its just
> > about
> > > gone.
> > >
> > > I must join with Adam and George in telling you that my new IC 756
> > Pro II
> > > has provided me with amazing frequency accuracy and repeatability.
> > And to
> > > those of you commenting that it does not matter I beg to differ. It
> > matters
> > > to many of us a whole lot. I simply got sick and tired of always
> > being off
> > > everyone else's frequency. It also matters if you want to work MARS.
> > Check
> > > out the MARS rig requirements of late.
> > >
> > > I will also add that some of the snide comments including "sell your
> > Omni
> > > and keep you Jap rig then you won't be so stressed out" once again
> > > demonstrate to me the developing intolerance of some on this list.
> > > Regrettable.
> > >
> > > I have both ICOM and Ten Tec gear here now but hold no blind
> > allegiance to
> > > any manufacturer.  Competition breeds the best product for us all. To
> > each
> > > his own. This specific problem was/is important to me and many others
> > who
> > I
> > > have spoken with but who care not to comment on the reflector.
> > >
> > > And on a final unrelated note, I wish TT would put some good quality
> > Orion
> > > photos on the TT Web site.  It needs to be seen better than is being
> > shown.
> > >
> > > 73 de N1LQ-Dave
> > >
> > >
> > > _______________________________________________
> > > TenTec mailing list
> > > TenTec@contesting.com
> > > http://lists.contesting.com/mailman/listinfo/tentec
> >
> >
> > _______________________________________________
> > TenTec mailing list
> > TenTec@contesting.com
> > http://lists.contesting.com/mailman/listinfo/tentec
> >
>
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec


<Prev in Thread] Current Thread [Next in Thread>