Absolutely agree on all points Lee.
Wish I could afford an Orion right away. Sure did drool
over them at the hamfest ! :)
Gary
----- Original Message -----
From: "WA3FIY" <wa3fiy@radioadv.com>
To: "George, W5YR" <w5yr@att.net>
Cc: <TenTec@contesting.com>
Sent: Tuesday, October 29, 2002 2:39 AM
Subject: Re: [TenTec] Receivability
> On 28 Oct 2002 at 22:19, George, W5YR wrote:
>
> > Very interesting, Gary, and thanks!
> >
> > I have made detailed spectral comparisons between the IF DSP filters
> > in the ICom 756 PRO, the Kachina 505DSP of similar architecture and
> > the Icom 765 with conventional crystal filters. There is no comparison
> > whatever between the shape factors and overall shapes of the PRO
> > filters compared to any of the others. The PRO filters are
> > mathemeticallu nigh perfect in shape and performance. I think that you
> > have found that the Pegasus IF DSP filters are not the equal to the
> > conventional INRAD filters - that is very surprising to me.
> >
> If you put things in perspective, I don't think it's at all
> surprising that 20 poles of Inrad in a Corsair and the DSP
> filtering of the PRO are superior to the Pegasus. It all boils
> down to one word..........COST.
>
> In the first place I don't believe TT intended the Pegasus to be
> a serious contest radio, and did not design it for that purpose.
> In it's day and even today if you discount it's lack of digital
> VFO's etc and add 20 poles of Inrad filtering, the Corsair is a
> contest radio.
>
> The Kachina and 'PRO both have more DSP horsepower to apply
> to the filtering process so they too should be superior in that
> regard.
>
> The Pegasus on the other hand at approximately 1/3 the cost of
> the 'PRO and 1/2 the cost of the Kachina, uses one 16 bit [I
> think] DSP processor to not only do the filtering functions, but
> also to control all other digital activity. So it has a limited
> amount of time to devote to filtering and then goes on to other
> assignments. Only Ten Tec knows if it is maxed out or not. Add
> an outboard SCAF or DSP filter and you will be close to the
> performance of the other radios and still be under their cost.
>
> The Orion of course is designed to be a contest grade radio and
> addresses these matters by giving the receivers two 32 bit DSP
> processors and two general purpose microprocessors to take
> care of other matters. No lack of horsepower here, and from
> the looks of things, it will give Gary's Inrad Corsair a good run
> for its money. :-).
>
> -73-
>
> -Lee-
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