Looking at the EBAY listings for the interface this is the path from the
line out to pin 1. (ASCII art schematic below)
PC OMNI VII
o-------oo---------o. .-o-------o
.-. )|(
| | )|(
2.2k | | ) (
'-' )|(
o--------o---------o' '-o-------o
600:600
Assuming the laptop is outputting LINE voltages (~.7RMS or 1Vpp into 600
ohms or 0.8mW).
The 2.2K resistor will change the impedance the laptop is seeing to 470 ish
ohms. Assuming the Pout is constant, the Vrms the Omni is seeing should be
around 0.6V or 0.87Vpp at max volume level.
Can you verify that is true?
On Wed, Aug 13, 2014 at 10:03 AM, Brian Carling <bcarling@cfl.rr.com> wrote:
> Not with digital sigs
>
> Best regards - Bry Carling
>
>
>
> > On Aug 13, 2014, at 9:13 AM, "Gary - AB9M" <glhuber@msn.com> wrote:
> >
> > Can you get the OMNI-VII to produce 100W via the Tune / PWR buttons on
> the frequency of interest and antenna used?
> >
> >
> > 73 & DX,
> >
> > Gary - AB9M
> >
> > -----Original Message----- From: Louis Ciotti
> > Sent: Wednesday, August 13, 2014 8:00 AM
> > To: bcarling@cfl.rr.com ; Discussion of Ten-Tec Equipment
> > Subject: Re: [TenTec] Omni VII Digital
> >
> > You should be getting way more power out that 20-30 watts. something
> > is just wrong.... you should be able to full power out in the
> > digital modes. Granted some of them there is totally not a need for
> > full output power like PSK-31, JT65, etc. At then end of the day if
> > you are not able to drive the OMNI to 100watts with all the settings
> > maxed out (both on the PC and the rig) something is wrong.
> >
> >> On Wed, Aug 13, 2014 at 7:52 AM, <bcarling@cfl.rr.com> wrote:
> >> It may be "fried" but I seriously doubt it. I was able to work into VK
> this morning on 40m
> >> with JT65 and I am now getting 30 - 50 watts output.
> >>
> >> The fault may be in the amount of signal WINDOWS 8 is allowing to come
> out of the laptop.
> >>
> >> I am trying to find if there is some level that is pulled down but
> everything I see is at 100%
> >>
> >> So far so good. I don't want to get 100 watts out and I think that I
> probably don't want any
> >> ALC action while running digital modes. The speech processor actually
> helps alittle in my
> >> case.
> >>
> >>> On 12 Aug 2014 at 23:12, Bob McGraw - K4TAX wrote:
> >>>
> >>> The Omni VII does not have low gain. But it seems yours has a
> defective
> >>> LINE INPUT. I can run mine at 25% and raising the level up on the
> computer
> >>> I get 100 watts of data output, well into ALC range.
> >>>
> >>> Sorry Brian, but from what you say, your LINE INPUT circuit is fried.
> This
> >>> is also evident from your findings that it works OK with the FT857 but
> not
> >>> the Omni VII. In doing a bit of research on the FT857D I find the
> audio
> >>> levels for the two radios are very close to the same values.
> >>>
> >>> 73
> >>> Bob, K4TAX
> >>>
> >>>
> >>>
> >>>
> >>> ----- Original Message -----
> >>> From: <bcarling@cfl.rr.com>
> >>> To: "Louis Ciotti" <lciotti1@gmail.com>; <tentec@contesting.com>
> >>> Sent: Tuesday, August 12, 2014 10:49 PM
> >>> Subject: Re: [TenTec] Omni VII Digital
> >>>
> >>>
> >>> > Nothing is smoked. The Tentec just has VERY low gain on that aux
> input
> >>> > when used in USB
> >>> > mode unfortunately.
> >>> >
> >>> > If I run everything flat out, I can make contacts. OMNI VII Line
> Gain > 100%
> >>> > Software level at maximum. Laptop gain 100% and OMNI VII Power set
> for > 100
> >>> > watts.
> >>> > If I run the speech processor at 40 - 50 I can make more power and
> more
> >>> > contacts.
> >>> >
> >>> > It works. It just doesn't work very well compared to an FT857D.
> >>> >
> >>> > If I turn the Keying loop back, on I can use my Centurion amp and
> get > 30 -
> >>> > 100 watts out
> >>> > depending on the audio frequency. The laptop produes a peak around 2
> > kHz
> >>> > which isn't
> >>> > unusual. With everything flat out 100% I can sometimes now get 20-30
> > watts
> >>> > out of the radio
> >>> > that way. Not great but it will do for now.
> >>> >
> >>> > On 12 Aug 2014 at 23:12, Louis Ciotti wrote:
> >>> >
> >>> >> On Tue, Aug 12, 2014 at 7:38 PM, <bcarling@cfl.rr.com> wrote:
> >>> >> > I don't think it's the signal levels unless there is a bad >> >
> connection
> >>> >> > insid ethe Easy-DIGI or her
> >>> >> > connected it to the wrong pin on the ACC1 cable.
> >>> >> >
> >>> >> > There is plenty of audio coming out of the laptop.
> >>> >> >
> >>> >>
> >>> >> Sounds like you are using the speaker output connection, typically
> >>> >> this output well above line level voltages (I am guessing here
> since I
> >>> >> have never probed the outputs on a laptop). I am placing my bet on
> >>> >> one of two things... either something is wrong with the interface
> or
> >>> >> you damaged something in the audio input circuitry. It sounds like
> >>> >> you are able to use this interface with another radio. If so then
> >>> >> something is smoked in the Omni audio input.
> >>> >>
> >>> >> Sounds like tou have access to an oscilliscope. Open up the
> interface
> >>> >> a probe the audio on one side of the isolation transformer (the wire
> >>> >> maked PC input) and compare that to the output side of the isolation
> >>> >> transformer. Report the peak-to-peak values back. Then probe pin 1
> >>> >> on the interface connector. Should match the output side of the
> >>> >> isolation transformer. If possible I would sent it a constant
> >>> >> frequency tone. that way you can get a nice sine wave to see on the
> >>> >> oscilliscope. If all is good there then it is pointing to something
> >>> >> in the radio.
> >>> >>
> >>> >> Lou
> >>> >> K2LRV
> >>> >
> >>> >
> >>> > _______________________________________________
> >>> > 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
> >>
> >>
> >> _______________________________________________
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