My Icom PRO with its 36 KHz IF and my Kachina with it 40 KHz IF certainly
do not have any flies on them compared to my conventional quadruple
conversion Icom 765.
In fact, in most instances, they both are superior radios in performance.
The idea that low IF's for DSP is bad is not correct. What is bad is not
knowing where and how the DSP should be used in the system. If it is tacked
onto the tail end of a conventional radio like some of the better known
"DSP" radios are, then it is little better than an outboard audio DSP. It
must operate within and control thereby the AGC system, etc.
A major difference between the Kachina and the PRO that shows up readily in
the shape of the IF DSP filters, for example, is the number of bits in the
DACs and the processing word-length. The Kachina uses 16-bit data and
24-bit processing, while the PRO uses 24-bit data and 32-bit processing.
The PRO filter shapes are remarkably better.
As CPU cycles and memory bytes get cheaper and cheaper and processors get
faster and faster, it is just a matter of time until the first DSP radio
comes out at affordable amateur prices with a 400-500 KHz DSP IF system, if
not higher.
I agree with Carl: the ORION is almost certainly a "full DSP" design. If it
isn't, then TT has lost a golden opportunity to grab the lead in the 21st
century amateur market before the IYK guys get there. And they are running
hard, believe me.
72/73/oo, George W5YR - the Yellow Rose of Texas
Fairview, TX 30 mi NE of Dallas in Collin county EM13qe
Amateur Radio W5YR, in the 56th year and it just keeps getting better!
QRP-L 1373 NETXQRP 6 SOC 262 COG 8 FPQRP 404 TEN-X 11771
Icom IC-756PRO #02121 Kachina #91900556 IC-765 #02437
All outgoing email virus-checked by Norton Anti-Virus 2002
Duane Grotophorst wrote:
>
> I'm not sure that all of the details are already cast
> in stone (or is that silicon?) so some "should we
> include it" or not kinds of decisions for little
> feature niceties may still yet to be made. However I
> do agree with Carl that it is very likely to be DSP
> IF, what remains to be seen is the choice of A/D bits
> DSP processor choice etc. Or if it will be borrowing
> heavily from existing DSP designs.
>
> I'm also puzzled why there is such a disgust for low
> IF frequencies? Especially with todays DSP technology.
> Personally I would lean toward a direct conversion
> arrangement a la Collins 95S-1.
>
> Duane
> N9DG
>
> --- Carl Moreschi <n4py@earthlink.net> wrote:
> > The RX340 is full blown DSP and it's the best
> > receiver I've ever seen.
> >
> > One thing to mention on this wish list stuff. I'm
> > sure whatever the "Orion"
> > turns
> > out to be, its been in developement for about the
> > last 2 years and
> > everything has
> > already been decided upon. I'd also be very
> > surprised if it wasn't anything
> > except full blown DSP.
> >
> > Carl Moreschi N4PY
> > Franklinton, NC
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