Well, let's look at the other side of the story:
If a system can be updated or re-defined by a single ROM flashing, then
this suggests strongly that the system is fairly unsophisticated in that it
can function from the contents of a single ROM. Small systems like the
Pegasus and Jupiter and even the Kachina use only a single micro-processor
that works from a single ROM and thus it is feasible to make such changes
as are possible with firmware updates, etc.
Why isn't the PRO updatable the same way? Mainly because it is a much more
complex system containing not only a dedicated DSP processor chipset but
also some 5 or 6 other uprocessors in various parts of the radio, and each
of them has burned-in ROM instructions. If all of these processors were
operated in a distributed network, not only would the system complexity
greatly increase - along with the cost - but operating speed could become
compromised unless some pretty fast busses and memory devices were used.
Distributed computing is nothing new, and networks are old hat, but how to
use these in a complex radio system and still control costs and provide
real-time performance can be a major design problem. And solving those
costs moeny - big time!
Personally, I am very pleased that my PRO cannot be "upgraded" with a PC
card change or the like. My Kachina could be - and yet the PRO runs rings
around the Kachina due no doubt in part to its use of multiple dedicated
processors not necessarily operated in a distributed network with the
overhead and expense that implies.
I think that this whole idea of "software-defined" radios has gotten way
out of hand and divorced from reality. The fact that a radio may be largely
*controlled* by software does not equate to its being a *software-defined*
radio. In order to remain current and to add many types of new features and
capabilities, at least some of the existing hardware must be replaced,
either by modification or substitution. This calls for a modular
construction which can be much more expensive than more conventional
layouts. For an example, compare the extensively shielded modules used with
the complex backplane structure of the Kachina 505 DSP with the
implementation of the Pegasus. Yet, when a fairly minor change was made in
the Kachina to upgrade the Speech Monitor among other things, one was
required to purchase a new $400 module and firmware and a new software
control program to enjoy those advantages. Then they stopped making HF
radios . . .
When our radios consist of high-speed ADC/DACs hanging off the antenna
terminals with ALL signal processing functions done in software, then
perhaps we can talk about software-defined radios. Until then, a practical
amateur transceiver must comprise a good deal of discrete hardware and
circuits which software perhaps can switch in and out or change settings,
etc., but as long as we are blessed with this hybrid world of software and
supporting hardware, let's be honest and call them "software-controlled"
radios, which they truly are. But software configurable? We are getting
closer and closer every year - witness the huge growth in the use of menus
for defining radio parameters and operating conditions - but we aren't yet
to the point where marketing can claim that their product is truly a
software-defined radio.
Tim and I are in full agreement on one thing, though: those @#$%^ green
legends on the PRO numeric pad keys! The penalty of "doing black" and not
being tacky with contrasting lettering is the hard-to-read panels we have
on so many radios today.
73/72/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 I-LINK 11735
Icom IC-756PRO #02121 Kachina 505 DSP #91900556 Icom IC-765 #02437
All outgoing email virus-checked by Norton Anti-Virus 2002
cyr999@extremezone.com wrote:
>
> Hi folks -
>
> One thing that I think TenTec is REALLY smart about is the flash rom. My
> 756PRO
> cannot be updated by flash rom. Instead, you get stuck with having to buy the
> "next generation 756" and your current generation suddenly drops in market
> value. That's good if you buy the one that dropped, but rotten if you want the
> latest changes. Icom's practice of doing this is my biggest objection to Icom.
> With TenTec's approach you feel like the rig could be current for a good
> number
> of years.
>
> In another vein, as many of you have mentioned, the OMNI's are TOTALLY user
> friendly and the face plates are very easy to read. However, the ICOM 756 is a
> no brainer to operate and very intuitive (thus pretty competitive in that
> area)....you don't really need the manual. On the other hand it's A REAL PAIN
> to
> read sum of the "green on black" numbers - too small and poor color choice.
> I'm
> amazed that they cannot make an easy to read radio face!
>
> Just a few more thoughts. 73/Tim Logan KB7OEX
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