Instead of assuming a dedicated microprocessor embedded within the
radio, consider an architecture in which the software runs on your PC,
which is connected to purchased (or home-brewed) external hardware via a
Firewire (IEEE-1394) connection. The external hardware is the minimum we
need to convert between RF and digitized data (I and Q): bandpass
filters, RX and TX RF amplifiers, an A/D, a D/A, a synthesizer, and
mixers.
With the exception of a QRO TX RF amplifier, the only "expensive" parts
of this system -- the firewire interface, the A/D, the D/A, and the
synthesizer -- can be inexpensively implemented with high-volume parts
from the consumer PC, digital imaging, and/or telecom worlds. You'll
already own the PC.
Much of the differentiation between competitive products will thus be
software that runs on your PC. Hams will of course be free to develop
such software themselves, either from scratch, or on frameworks that
provide basic capabilities with support for customization and
experimentation.
My prediction: within 3 years, you'll be able to purchase a QRP
transceiver in the above configuration for under $200.
73,
Dave, AA6YQ
-----Original Message-----
From: tentec-bounces@contesting.com
[mailto:tentec-bounces@contesting.com] On Behalf Of John Rippey
Sent: Friday, November 28, 2003 08:18
To: tentec@contesting.com
Subject: [TenTec] Waiting for Transceiver Nirvana
While waiting for zero hour of the CQ WW CW contest, these thoughts
occur
on the recent postings re software-driven base station rigs.
1. They are (with the odd exception of the IC-746PRO) damnably
expensive.
If it's not the chips that make them so, then it is the humungous
engineering effort needed to make them work well.
2. If Moore's law still prevails, then any chip chosen for a
software-driven radio will be replaced in 18 months by one that is half
as
costly and that has twice the computing power. Ergo, much more so than
with
the analog rigs we know and love, rapid obsolescence of the latest and
greatest software-driven rig is a given.
3. Because the ham market is downscale with regard to pricing, we do
not
see the performance in ham market software-driven transceivers that is
available up-market. Compromises in ham gear necessarily are made: in
selection of chips, and in their engineering, to meet the ham market
price
point (ICOM obviously will be testing the upper limits of the ham market
with its IC-7800). There are all kinds of compromises in the ICOM PROs,
and
so also in the ORION, hence the discussions on this and other
reflectors.
4. Therefore, while we may like to think we are seeing in the latest
rigs
the absolute latest and greatest--we aren't, and we won't. After all,
we're
radio amateurs.
5. The bad news is that as advances in this genre gradually trickle
down
to hams, the resulting rigs will be expensive (by ham standards), their
performance will be markedly better than their predecessors, and we'll
repeatedly have to dig into our pocketbooks to pay for that performance
if
we just cannot live without the next new thing.
In short, chasing after transceiver nirvana is going to be an expensive
fling. I may opt out.
73,
John, W3ULS
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