From: Joel Kolstad on Wed, Feb 22 2006 10:30 am
wrote in message
If we look at what exists now, we get blase' about all the effort
involved to make a product (almost as if "it always existed...")
available for others to use. Too many of us take the THINGS we
have for granted.
When you can run down to the local computer store and buy something like a
wireless router containing a 54Mbps digital radio with very sophisticated
modulation schemes running from some embedded CPU with the equivalent
horsepower of an 80386 with 64MB of RAM, all for $39.99, I can see why. :-)
Microchip Semiconductor will tell everyone the same about their
PICs (or Atmel about theirs)...and you have a good analogy! :-)
But, as some 1950s-technology hams may grouse, "that's not RADIO!"
[I've heard that bs way too often...grrrr] Those folks can go
look into the Analog Devices ICs such as their various DDS or
log-amp-detectors, all definitely working at RF, not "digital."
Or some of the old (pre-split-up) Motorola definitely-analog
complex arrays for various functions at RF, some still made and
available 30+ years after first introduction. PLL by itself has
made "boxes of rocks" (quartz crystal units) relatively obsolete
after becoming state of the art in communications electronics
around 1970. Look at the 1 GHz RF in cellular telephony and
cordless phones operating at 5 GHz...I got into "pro" leagues
in microwaves at 1.8 GHz in 1954, thinking that a 6-wide rack
of radio relay equipment (using tubes) was "hot stuff"...only
to think of regular use of a 2.4 GHz cordless handset as being
"ordinary, everyday thing" 50 years later.
Hey, the huge electronic supermarket called Fry's is just a
mile and a half from my house here. Lots of low-cost, very-
high-tech "toys" available in there.
What "the universities" do is NOT NECESSARILY what goes on in
the rest of the world! True, despite the self-promoting PR of
"the universities!"
Very true, although I think that many univerisites have found -- in the past
couple of decades -- a need to become somewhat more aligned with industry in
order to continue to procur funding.
If they want to TEACH students what goes on in industry of the
day, absolutely. They've gone insular amongst themselves in
the last few decades...in the teaching part of their activity.
As far as IP protection on radio hobby magazines, that's
still up in the air for many. If everyone wants to sit
around and rebuild the regenerative receiver or "design"
two-tube (or teeny two-transistor) transmitters, fine, but
that is just re-inventing the wheel for the nth time.
It is, although it can serve as a great educational tool for the person doing
it. Since ham radio is -- for most people -- a hobby, re-inventing such
radios is about the same as someone rebuliding the engine or transmission on a
classic car: The end result is still not going to be as, say, fuel efficient
or powerful as a modern design, but someone who understands the basics is then
a very large way towards understanding the modern design... if they have any
desire to do so.
That's true, yes, but those hobbyists have to stay within their
own group to praise their work amongst themselves. I like
some nostalgic things well enough, but I've already lived
through (and worked in) the radio-electronics technology of
the 1950s and do NOT think such is very close to state of the
"radio" art of NOW.
When you go to student engineering design expos these days, there's usually
plenty of wireless interfaces to robots, data collection devices, etc.;
they're almost always implemented with a little wireless module where you feed
in digital data, and everything else all the way to the antenna is a black
box. What you almost never see is something like a discrete transistor radio
design implementing, say, BPSK at 1200bps (which often would suffice for the
wireless data transmission needs).
A discrete transistor radio would be too bulky for that purpose.
Also a bit higher on the portable power source demand. :-)
I finally got around to fixing and cleaning up an "old" Sony
AM BC radio that was beloved by my late mother (the D cells
had all stayed in and leaked out while she was ill). Great
AM radio, very sensitive due to an added RF amplifier stage
(rare in designs of 30 years ago and now). [it's so "old"
that the push-pull linear AF stages used coupling transformers]
About the same time my wife got an under-the-cabinet AM/FM/CD
radio for her sewing room station (one wall of a guest room).
That radio has a SINGLE IC that does the PLL functions for
both AM/FM LO frequency control, all the RF-IF-detector stages,
AND includes the time-of-day clock PLUS the LCD display
functions! That IC is only available in very large quantities
(from Asia) but it shows the tremendous amount of mixed-signal
capability of a single IC nowadays.
Although I find this a little lamentable,
I realize that these days indsutry needs a lot more people creating such
system- or IC-level designs (rather than, say, 50 years ago when I'd expect
that most "electrical engineers" found themselves performing discrete
transistor -- or tube! -- design), and I also realize that industry still
seems to find graduates who become good RF IC designers, so clearly the
problem isn't as bad as I might imagine and is probably more a reflection of
just becoming set in my own ways instead! :-)
Well - despite being (originally) a "mustang" EE who DID do
discrete tube and transistor stage design - the electronics
industry has tons of already-designed ICs for various RF
purposes and the folks who thunk them up. The problem is more
that they came about for MARKET SPECIFIC applications. Right
now one can get almost anything needed for cell phone designs,
including the cell site stuff...it has been the market driver
for a few years. Maybe automotive electronics is next (some
applications using RF for "wireless" things like tire pressure
measurement while rolling)? PCs are old hat in the industry
since the user market is starting to get saturated.
Case in point for HF range transmitters: Asian designs for CB
finals were already in production (in lots of thousands-plus
per model) and being sold (by the tens of thousands) before
1970. Motorola started pushing power at HF, avoiding CB but
going below and above it in frequency, having lots of designs
of PA transistors of some power. Helge Granberg of Motorola
bossed a lot of detailed, good Appnotes on the how-to and
how-come aspects of various power amplifiers. [Communications
Concepts has the ANs available and sells most of the "MRF"
power transistors now] Motorola didn't sell as many as they
thought and eventually dropped that line (before the double
split into ON and Freescale). Yet Asian designers were, at
the same time, turning out amateur radio power amplifiers in
the 100 to 200 Watt category, lesser power outputs on VHF
on their own. Nowhere can be found the depth of detail on
design of those Asian HF power amp designs, but the Motorola
Appnotes are still studied (even if the "MRFs" are getting a
bit scarce). The detailed information EXISTS, but it doesn't
exist for public distribution. The market doesn't allow it.
Much
of the output of the radio hobbyist press (other than new
product info squibs and "reviews") is the publishers
essentially copying their own old works...for their own
profit.
Sure, or someone taking an old design and adding a microcontroller
interface/LCD/etc. (Seems to crop up a lot with auto-tuners, power meters,
etc... I've been tempted to do one of these myself... something like a mobile
2m amplifier for an HT... 300mW in, 30W or so out, with digital display of SWR
or whatever... clearly the "core design" of the amplifier and SWR meter has
been around for decades now...) Granted, a lot of any "new design" is just
modifying old designs with various new ideas, but the ARRL's standard to
publish a "new" article is perhaps rather low.
Well, in my view, there's too much ham emphasis on transmitters
and power and mechanical aspect of things. Some other things
have been neglected, but taken up by others selling a product.
Another case in point: Neil Hecht's neat little frequency
displays out of AADE in Seattle. No more than three ICs
(all DIP) on a board plus a 2 x 16 LCD character display
module. The main ingredient is a PIC microcontroller that
does both the frequency counting (!), the display module's
input, AND (optionally) a compensation for IF offset in
multiple-conversion receiver/transceiver models. It can be
mounted IN just about any boat-anchor (or smaller) HF
transceiver and functions the same as a many-IC frequency
counter. Strangely enough, it was "pioneered" NOT by a ham
but a UK experimenter who was interested in getting a simple
frequency counter. The Internet allowed the idea to spread
all over the world. The microcontroller source code for
similar units can be obtained (most places for free) but you
need a programmer to stuff the code into the microcontroller.
Or, find someone to do the PIC's ROM code burn-in for you.
I bought an AADE L/C-Meter recently. Assembled, noting the
extra cost wasn't all that much. It saved adding to my
hobby workload. It is based on the same PIC microcontroller
(but with different code). AADE publishes the schematic
and component details. Had I bothered to learn the PIC
instruction set (prodigious even if RISC), I could have
done the programming myself...after about a thousand hours
of fooling around with routines versus hardware. It was
much easier for me to BUY the whole works, leaving precious
time free for other things.
What's missing is some reasonable means of licensing IP to people who want to
use it on a hobbyist basis.
A lot of that IP is already free. A major problem is that
there are too many kinds of programming conventions for
source codes. Few can be "expert" in all of them. Usually
one can be "good" in only one, realistically speaking. As
an example, Microchip has lots of utility routines of
various kinds for free on their website...but one needs to
know the PIC instruction set to make sense of them.
In source code it would be (in my view) better to show the
program flow rather than the code itself. That way anyone
can translate flow into the particular source code they
know. Oddly, most hobbyist programmers don't like to show
flow diagrams...those aren't as "cool" as source code
statements neatly arranged by the source code development
program. :-(
On the upside, today it's easy to purchase RF components that allow one to
build radios that have better performance and are cheaper to build than ever
before.
Absolutely!
It's the hardware--software interface -- with software defined
radios starting to become commonplace -- where you can't just go to DigiKey
and purchase a CELP software license off the shelf; this is one of the
problems holding back the development of ham radio.
I don't quite agree with the gist of your argument. SDR is
the new buzzword and it can certainly apply to digital-based
communications (cell phones, etc.) but not necessarily to
the analog HF world.
MOST of the transceivers for amateur radio, HF to UHF, are
ALREADY software-controlled, courtesy of a built-in micro-
processor or microcontroller. For PLL or DDS frequency
control AND display of same, that is a necessity to achieve
incredible (to 1950s standards) frequency control. That
same little digital subsystem can do myriad other tasks to
eliminate the physical mechanics of construction. The
multi-wafer rotary bandswitch disappeared from ham
transceivers on the market decades ago...and it's hard to
get the parts for such rotary switch assemblies now for
any electronic purpose except high-current switching.
Because that ubiquitous internal micro has become so
commonplace, it has led to a "radio box" that is controlled
by a PC. That's a natural extension of the internal
digital control already present. But, having the PC
display the equivalent front panel does NOT make it an
SDR! It's a neat selling point, makes it LOOK high-tech
and "the latest thing" but the PC-controlled "radio box"
is really just another version of the existing manually-
controlled HF transceiver.
IF - and only IF - amateur radio voice communications goes
digital on HF will there be any real need for SDR in ham
radio "bands" (the ones on HF). Right now the existing
analog-only amplifiers and whatnot are mature and quite good
enough. One problem with digital voice is that there isn't
even a hint of a standard protocol or of many experimenters
yielding any results on same. The Data modes allocated now
can make do with peripheral adapters since they are not yet
that numerous on HF.
Granted, hams could --
and do -- development a lot of these things themselves, but given their
technological sophistication, ham radio will now more than ever have to follow
commercial standards (as they have with FM, NTSC for ATV, etc. -- it's been a
_looonnng_ time since ham radio was _setting_ the standard, although the APRS
guys do like to point out that a lot of commercial systems today still aren't
as good as they are).
Well, if we dwell on such true facts, it will lead to toxic
levels of acrimony in here. :-)
Back to watching HDTV from the Winter Olympics in Turin...