I have compared the Timewave 59+ and the JPS NIR 12 with TT's inboard
Omni VI+ DSP. (As far as I could tell, the difference between the 59+
and the 599zx are the controls.)
On CW, the Omni VI+'s seemed to do a better job of increasing the volume
of the desired signal than did the 59+. The 59+ does a creditable job of
lowering background noise without increasing the desired signal. So if I
turn on the 59+ and increase the volume, the units are comparable. I see
no reason to use the 59+ with the Omni VI+. (I use it with my Corsair
On SSB, the NIR 12 does a better job of reducing noise than either the
TT or the Timewave. But it introduces a time delay that makes sending CW
difficult. So I use it with my Omni VI+ on SSB only.
Neither unit is very expensive now, especially in comparison to what you
have already invested. It would be worth a try. Please keep us posted.
Jim Reid wrote:
> Hi all,
> Have had the 340/Pegasus set up for about a month now.
> Biggest "con": no DSP noise reduction option!!
> The Omni VI+ has a beautiful NR function, particularly
> for CW, but nothing on the 340. Where I live, there is
> essentially no "man made" RF noise to worry about, but
> we are also a loooong way from any DX (Hawaii is the most
> isolated QTH on the planet, nothing closer than a few
> thousand miles). So, DX is often weak, lots of F layer
> hops to get here, but bounces off the ocean help, hi.
> Anyway, I wish for my Omni NR button back! Now, would
> a Timewave 599zx substitute?? The 340 AGC, is wide open
> on a dead band, and the audio noise output is very high.
> Connecting to the dummy load, still a lot of noise out.
> The 340 meter reads at the noise floor, - 135 dBm or so,
> but the IF and audio gain bring it up loud.
> The Timewave specs specify the DSP noise reduction is
> about 20 dB. If I turn down the "RF" gain of the 340 20 dB,
> I don't see a really noticeable noise reduction, but this might
> not be the same thing. Don't know what the NR reduction
> in the Omni VI+ using their algorithm might be; ARRL did
> not test it in the 1997 review, nor is their any info in their
> "expanded" test report about the DSP NR in the Omni.
> So, is it a good idea to buy a Timewave to mate to the
> 73, Jim KH7M
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