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Re: [TenTec] Omni Vi and DSP

To: tentec@contesting.com
Subject: Re: [TenTec] Omni Vi and DSP
From: Duane A Calvin <ac5aa@juno.com>
Reply-to: Discussion of Ten-Tec Equipment <tentec@contesting.com>
Date: Tue, 17 Jan 2006 09:02:25 -0600
List-post: <mailto:tentec@contesting.com>
I believe the bypass circuit was added to the DSP-9+ because so many
folks had problems when their DSP-9 was running on very narrow bandpass,
and the CW monitor tone was outside that bandpass.  Hence the need to
open it up (or bypass it) on transmit to hear your own monitor tone.  The
DSP-9's had practically unnoticeable time delay in its path.  

By the way, The JPS units with NIR actually had significant delay due to
the "NIR" design.  The NIR-12 had 2 types of noise reduction, one I'd
call "frequency" based, and one I'd call "time" based.  The time based
one introduced the delay, and I rarely found it useful.  To my ear, the
'frequency based' noise reduction algorithm was significantly better
sounding than the Timewave's.  FWIW.

        73,  Duane

On Tue, 17 Jan 2006 07:21:44 -0600 Robert & Linda McGraw K4TAX
<RMcGraw@Blomand.Net> writes:
> I haven't observed a problem in operating  CW QSK with the DSP-9+.  
> As with 
> any digital processing means, there is and will be a processing 
> delay. 
> Timewave states that it is adaptive at 30 msec max.  (0.030 sec}
> Now what you may need to do is connect the PTT jack on the DSP-9+ to 
> the NO 
> relay jack on the back of the Omni VI Plus.  Be sure to activate the 
> relay 
> function in the menu.  This will take the DSP processing out of the 
> circuit 
> during transmit thus allowing the sidetone to pass.
> 73
> Bob, K4TAX
> ----- Original Message ----- 
> From: "John/K4WJ" <k4wj@bellsouth.net>
> To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>; 
> "Discussion 
> of Ten-Tec Equipment" <tentec@contesting.com>
> Sent: Tuesday, January 17, 2006 6:49 AM
> Subject: Re: [TenTec] Omni Vi and DSP
> > Bob,
> >
> > Can the DSP-9+ be used with QSK or is there no way to disable the
> > delay in the audio signal?
> >
> > 73..de John/K4WJ
> >
> >
> > At 10:53 PM 1/16/2006, Robert & Linda McGraw K4TAX wrote:
> >>The Omni VI Plus DSP has two functions.  One is noise reduction NR 
> and the
> >>other is Auto Notch.  The NR algorithm is tailored basically for 
> SSB noise
> >>reduction with minimal impact on voice.  It works equally well on 
> CW.  The
> >>AutoNotch is just that.  It looks for and at constant tone values 
> and
> >>rapidly creates a very sharp notch of some 40 dB, more or less 
> depending 
> >>on
> >>tone frequency and the number of notches it is required to 
> generate.
> >>
> >>As to external DSP units, I use a Timewave DSP-9+ with great 
> success.  It
> >>connects in-line between the external speaker output and the 
> external
> >>speaker.  The 13.8 volts is obtained from the rear panel 13.8 V 
> jack on 
> >>the
> >>Omni.  It offers several features that is not offered in the Omni 
> VI Plus 
> >>in
> >>addition to bandwidth shaping and decoding for RTTY mode.
> >>
> >>In either case both DSP systems are audio only processing, 
> therefore a 
> >>tummy
> >>full of 9 MHz IF filters and 6.3 MHz IF filters are of great 
> value.
> >
> >
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Duane Calvin, AC5AA
Austin, Texas
TenTec mailing list

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