The Omni VII is the singular odd man out as far as I know. In some of the
v1 versions of firmware, the Orion s-meter is also unaffected by RF Gain
etc setting, but that reverted to usual behavior in v2/v3.
Barry N1EU
On Wed, Apr 25, 2012 at 12:54 PM, chacuff <chacuff@cableone.net> wrote:
> I agree...I'm finding it crazy that the claims that the OII does not work
> that way is being brushed aside as us just not understanding. I've been a
> component level tech for nearly 40 years...I fix these things too as well
> as
> restore tube radio gear...from point to point to surface mount. I
> understand well...and on my OII "it just ain't so"...
>
> I'll be happy to do a short video of just how it reacts and post it if that
> would help.
>
> I do have a desire to understand why we are experiencing differences...
>
> Some of the confusion I think is that while we started this discusion on
> the
> model 566 suddenly three or four different Ten-Tec radios have been brought
> into the discussion assuming that they were all designed the same or that
> the software writers stayed true to the same functional requirement...which
> I'm sure they didn't.
>
> I brought the Omni VI+ into the discussion because there was a statement
> that that was the way all Ten-Tec radios were designed. I was fully aware
> that it was a traditional analog design.
>
> It is indeed hard to make comparisons between apples and oranges in any
> analytical way.
>
> Cecil
> K5DL
> ----- Original Message -----
> From: <kc9cdt@aol.com>
> To: <tentec@contesting.com>
> Sent: Wednesday, April 25, 2012 12:00 AM
> Subject: Re: [TenTec] 566 Orion II Firmware Version
> V3.029---SpectrumDisplay&Tuning...
>
>
> > The Omni VII obviously works different than OII.
> > 73,
> > Lee
> >
> >
> > -----Original Message-----
> > From: chacuff <chacuff@cableone.net>
> > To: Discussion of Ten-Tec Equipment <tentec@contesting.com>
> > Sent: Tue, Apr 24, 2012 10:17 pm
> > Subject: Re: [TenTec] 566 Orion II Firmware Version
> > V3.029---SpectrumDisplay&Tuning...
> >
> >
> > Bob something is missing here for sure.
> >
> > If I do exactly what you say my "S" meter does not react the same.
> > That is
> > on my Orion II with the latest firmware and with the earler 2.044 and
> > also
> > my Omni VI+. Add attenuation and the meter goes down. On the Orion at
> > preamp and the meter goes up. It's not broken it's just different and
> > we
> > haven't identified why.
> >
> > I agree with your assertion that that may be an ideal way for it to
> > work
> > because none of what you did with attenuation or preamplification
> > changed
> > the signal leve received at the antenna...but the fact is my rigs don't
> > work
> > that way.
> >
> > Cecil
> > K5DL
> > ----- Original Message -----
> > From: "Bob McGraw - K4TAX" <RMcGraw@Blomand.net>
> > To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
> > Sent: Tuesday, April 24, 2012 8:35 PM
> > Subject: Re: [TenTec] 566 Orion II Firmware Version
> > V3.029---SpectrumDisplay&Tuning...
> >
> >
> >> According to Art Collins, generally credited with the adoption of the
> > S
> >> meter system, it was intended to give meaningful signal strength
> > reports.
> >> The old "green magic eye" on radios was a tuning indicator. Yes, the
> >> original value per my Collins 75A-3B manual shows S-9 = 100 uV.
> >>
> >> Sitting here this evening in front of my Omni VII listening to WWV on
> > 10
> >> MHz, at 100% RF Gain the S meter indicates S-9 +6dB. Switching in
> > the
> >> ATTN
> >> in 6 dB steps to 18 dB the S meter stays at S-9 +6dB. The answer is
> >> simple.
> >> Add 18 dB of attenuation to the input, which automatically adds 18 dB
> > of
> >> gain to the S meter circuit. The opposite is true when the preamp is
> >> engaged. Add 12 dB of gain to the receiver circuit which
> > automatically
> >> adds
> >> 12 dB of loss to the S meter circuit. I refer to this as a smart S
> > meter
> >> system. SMART = Signal Measurement, Accurate, Reliable, True
> >>
> >> The Eagle, no matter what one does in terms of Attenuation or RF Gain
> > or
> >> Preamp activation, the S meter reading does not change. Again, same
> >> concept.
> >>
> >> Think about it, if you are receiving a station at S-9 + 20 dB and you
> >> switch
> >> in 18 dB of attenuation, did you change his signal strength at the
> > input
> >> of
> >> your radio? The answer is NO. You changed the signal at the input
> > to the
> >> receiver first stage. Then shouldn't the S meter always reflect the
> >> signal
> >> strength regardless of what one did to their receiver gain system?
> > Hence
> >> you can always be assured that the S meter system in the Tentec Omni
> > VII
> >> and
> >> Eagle will reflect the correct value at the input to the radio.
> >>
> >> Even with a signal at the input of -23 dBm or 15,811 uV which is 50
> > dB
> >> over
> >> S 9, reduction of the RF Gain to 0% the S meter does not change. It
> > still
> >> shows the signal at 50 dB over S 9, hence the system inversely adds
> > gain
> >> to
> >> the S meter circuit to make up for the reduction in RF Gain.
> > Therefore,
> >> the
> >> S meter is correct reading regardless of RF Gain setting. Of course
> > once
> >> you remove the 50 dB over S 9 signal with RF Gain at 0% you will see
> > the S
> >> meter display drop to 40 dB over S 9. The point being that the RF
> > Gain
> >> does
> >> not affect the accuracy of the S meter reading above AGC threshold.
> >>
> >> Now what one does see with no signal applied, as one reduces the RF
> > Gain
> >> the
> >> S meter moves upscale in 6 dB increments or 1 S unit. This reflects
> > the
> >> threshold of AGC reference to S 9 being 50 uV. At 100% RF Gain, as
> > one
> >> engages the ATTN function in 6 dB increments you will observe the S
> > meter
> >> indication move up scale 1 S unit per 6 dB. Now once reaching 18 dB,
> >> engage
> >> the Preamp and you will see the S meter move down scale by 2 S units
> >> indication that 12 dB of gain has been added.
> >>
> >> All of the math works and so does the radio respond accordingly.
> >>
> >> 73
> >> Bob, K4TAX
> >>
> >>
> >> ----- Original Message -----
> >> From: <k3miy@csonline.net>
> >> To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
> >> Sent: Tuesday, April 24, 2012 11:10 AM
> >> Subject: Re: [TenTec] 566 Orion II Firmware Version
> >> V3.029---SpectrumDisplay
> >> &Tuning...
> >>
> >>
> >>> You're right, Ray. In the old days, the S meter was regarded as a
> >>> tuning aid, and nothing else.
> >>>
> >>> Ron
> >>> K3MIY
> >>>
> >>>
> >>> Quoting Rsoifer@aol.com:
> >>>
> >>>> Not only that, but the old Collins spec was 3 S units = 10 dB, not
> > the
> >>>> modern standard of 6 dB per S unit.
> >>>>
> >>>> More broadly, I'm afraid I just don't understand the continuing
> >>>> preoccupation with S meter and spectrum display issues. Neither
> > has
> >>>> much
> >>>> to
> >>>> do with
> >>>> performance, which is where I'd like to see T-T focus their
> > attention.
> >>>> Flak
> >>>>
> >>>> jacket on!
> >>>>
> >>>> 73 Ray W2RS
> >>>> _______________________________________________
> >>>> TenTec mailing list
> >>>> TenTec@contesting.com
> >>>> http://lists.contesting.com/mailman/listinfo/tentec
> >>>>
> >>>>
> >>>
> >>>
> >>>
> >>>
> >>> -------------------------------------------------------------------
> >>> This mail sent through CSOnline Webmail http://webmail.csonline.net
> >>>
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> >>>
> >>
> >>
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> >>
> >
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