In article , Alun
writes:
(Len Over 21) wrote in
:
In article ,
(Brian Kelly) writes:
(Steve Robeson, K4CAP) wrote in message
le.com...
(Brian Kelly) wrote in message
om...
There's virtually NO new-mode experimentation going on anywhere in
any ham bands. We have high bands where all sorts of "multimedia"
wideband ops are already quite legal. But all we hear is the talk,
the walk simply isn't happening. Why would it be any different on
the HF bands??
Usually this mantra pops up by some of the no code faction who
has tried to promote the idea that "experimenters" in new mode
technologies would somehow come out of the woodwork IF there was
no code test to keep them off of 20M phone.
Go figure!
It's been something like twelve years since the first of the piles of
nocodes hit the bands 30Mhz. Mayber it's happened and I missed it but
I have yet to see or hear of a single example of a nocode
experimenting with a new wide mode. For that matter none of the Extra
"wideband digigeeks"who have bleated the same refrain have done
anything but talk either.
Is PSK31 chopped liver? :-)
Maybe you don't recognize Peter Martinez, G3PLX?
He was experimenting with polyphase shifting networks for SSB
back in 1973.
The original research paper on that particular topic was actually published
in 1945. I have a copy of it somewhere...
No doubt something was done back then. A former RAF boffin
named Clarke would have his geosychronous 3-satellite comm
proposal published in Wireless World a couple years later. I was
fortunate to read an original W.W. issue with that article. Right now
ALL of the geosynchronous orbit positions are taken... :-)
Mike Gingell did his PhD thesis on the polyphase network (the four-
phase version, not to be confused with other "polyphase" networks) in
the UK. I have a copy of that courtesy of a UK amateur.
Several picked up on that thesis in the UK and Martinez' version
was printed in Radio Communication magazine some time in 1973.
My boss at RCA (Jim Hall, KD6JG) showed me that and it looked
fascinating. I snitched some corporate computer time and
analyzed it in LECAP, the RCA frequency-domain version of
ECAP. I sent the results to Pat Hawker whose column ran the
polyphase stuff and that was published in 1974 in Radio
Communication.
Jim Hall is one of the "third-method" SSB innovators and his paper
done at RCA remains as a footnote mention in the "Collins SSB
book" although the authors got the third-method system
descriptions mixed up.
Several in Yurp have used the Gingell values with success for SSB,
including direct-conversion versions. One of Dan Tayloe's QRP
receivers (D-C) uses that. A Japanese amateur surnamed Yoshida
refined the values for even less quadrature phase error and that was
published in QEX. The Gingell-Yoshida value set is most forgiving
of component tolerances yet providing excellent very low error
quadrature phasing across the audio voice band.
Mike Gingell moved the USA and got a U.S. amateur license, was
living in an eastern state and was interested in satellite reception
according to his personal website.
It's now 31 years later and most U.S. amateurs are ignorant of the
Gingell circuit or haven't looked into it...most preferring to operate
their ready-built, designed-by-commercial-engineers equipment.
The (Gingell) polyphase circuit has also been the subject of papers
in the IEEE Transactions on Communications in the late 1970s and
1980s for applications other than SSB.
The basic PLL circuit was first described in 1932 (!) by France's
H. de Bellescize but it doesn't bear a lot of resemblance to the
modern PLLs using specialty ICs such as an MC145151. :-)
All things are as they were then except for some profound changes.
LHA / WMD