In the mid-80's there was an unsuccessful
consumer data-over-mediumwave service in the
U.S. I forget the name of the company offering
it, but it required the purchase of a demodulator
(one-way modem) to connect between the earphone
jack of your AM radio and the audio/data input of
your personal computer. Data was transmitted by
participating mediumwave (AM) radio broadcasters
in various formats compatible with various
personal computers of the day, which used audio
cassettes to store programs and data.
Stations would typically run the "show" late at
night, which was sponsored by
advertisers. Unfortunately this never took off
(this was a good decade before the internet was
readily available to general public.) One
station near Philadelphia that aired this data
program was WAWA in Wawa, PA -- whose owner Lloyd
Roach was later sued by Wawa Corporation for
trademark infringement (the village of Wawa, PA
existed long before Wawa Corp.) They beat him
with into submission with lawyers. Lloyd told me
the innovative radio data broadcast program was a
commercial failure, but I thanked him for trying it.
Around 1981 Radio Netherlands did a test
broadcast of various personal computers' audio
data. I recorded the TRS-80 data stream from my
Sony ICF-2001, but propagation caused signal
fading that prevented a usable tape recording
that could be decoded by a TRS-80
microcomputer. Radio Netherlands later reported
that none of its listeners who participated in
the test reported a successful computer program
download. But it was a pioneering effort.
-Ed Cummings
At 09:46 AM 2/6/2013, Joe Buch wrote:
The concept of transmitting digital information
on the same frequency as an AM audio carrier, as
Dr. Kim Andrew Elliott and Thomas Witherspoon,
will do at the Fest rings a vague
bell. Someplace I read that KFI, Los Angeles,
had a radio teletype signal superimposed on its
carrier by means of frequency shift keying
during World War II. The project was highly
classified as the information was being sent on
behalf of the War Department. The frequency
shift was small compared to the 10 kilocycle
bandwidth of the channel so an AM receiver would
not detect the frequency deviation unless the
receiver had a BFO and the receiver operator had
it turned on which would not be normal for AM
audio reception. KFI had and still has
excellent coverage of the Pacific Ocean area. I
have personally heard KFI on the northeast coast
of Kauai at 3 in the afternoon local time in August.
A Google search for this reference failed to
turn up anything. Has anyone else ever heard of
this project, and if so, can you supply a reference?
Joe Buch
N2JB
From: John Figliozzi <[email protected]>
To: Discussion list for the Winter SWL Fest <[email protected]>
Sent: Tuesday, February 5, 2013 3:25 PM
Subject: [Swlfest] Forums Schedule Update!
2013 Winter SWL Fest Forums âPreliminary Finalâ* Information
(*I think Rob DeSantos would like that description
)
Here is further information on the scheduling of
the forums and other key events on Friday, March
1 and Saturday, March 2 at the 2013 Winter SWL
Fest. Times are EST and in 24 hour format. All
forums, except the traditional Saturday Night
Shortwave Shindig, are timed for one
hour. Please be advised that this schedule remains subject to change.
Friday, March 1
0830 Registration and Exhibit Room
Open. (Hours of ooperation to be announced.)
0930 Economically Enhanciing Your Collection
thru Auctions and Flea Markets Ed Mauger
1100 From the WBCQ Archives Larry Will. A
combimbination visual, video and audio
presentation highlighting the most interesting
bits of the history of the now legendary
independent shortwave station WBCQ âThe
Planetâ, located in Monticello, Maine, and
itâs hundreds of programmers from the presenterâs point of view.
1200 Lunch on Your Own
1400 DXâing With a Dish Mario Fillippi.
sp; Beginning with the basics of Free to Air
(FTA) Satellite radio and television, this
illustrated session will cover station setup,
programs to be heard, satellites that are out
there for FTA, data on which satellites are best
for international reception, areas of the world
that can be accessed via FTA, etc., etc., etc.
1530 Antennas, Batteries and Computeers, Oh
My! Tom Swisher. Annually, one of our most
popular fforums, the inestimable (?!) Scanner
Scum will continue Scanner Basics from last year
by delving into effective portable antennas,
better batteries and interesting ways to use your computer with your scanner.
1630 â Drinks and Dinner (Maybe Dancing? Gosh, We Hope Not!) on Your Own
1900 Swap Meet
2000 - QRP: How Low Can You Go? Thomas
âUncle Skipâ Arey. International shortwave
broadcasters use thousands of watts and gigantic
high gain antennas to move their signals around
the world. Hams like Uncle Skip do the same
thing with 5 watts (or often less) and a random
length of wire. Learn about this low power (and
low cost) way to experiment with HF radio.
2100 The Friday Night Shortwave Shindig 10th
Anniversaary David Goren. Our popular,
oh-so-relaxed evening-long livve listening
event, conceived, developed and presented by
David with a little help from his friends, that
features archival shortwave sound, live
monitoring, and live performance of shortwave
radio related arts and culture. If youâve
missed out on this in the past, donât lose out this year!
Saturday, March 2
0830 Registration annd Exhibit Room Open
0915 Sounds from Space: Monitoriing and
Tracking Satellites Using HF Dave
Marthouse. How to monitor the various orbiting
satellites that can be found throughout the
frequency spectrum from hf through the
microwaves. These birds include weather,
navigation, amateur radio, military and
more. Monitoring these satellites can be done
for the most part with simple equipment (even
hand-held receivers and antennas)!
1015 â Silent Auction Opens
1045 Digital Text via Shortwave BBroadcast -
Kim Andrew Elliott/Thomas Witherspoon. Unless
youâve been more tightly closeted than usual,
you will have heard of the weekend tests being
conducted on The Mighty KBC demonstrating that
the digital text modes used by radio amateurs
(e.g. PSK31) can also be transmitted on analog
amplitude-modulated shortwave broadcasts. And
they can received by an inexpensive shortwave
radio, then patched to a basic PC for decoding,
using free software. Often when shortwave
reception conditions result in difficult
comprehension of voice broadcasts, digital text
can be received 100%, or nearly so. Digital text
via shortwave broadcast can fill in when the
internet is disrupted by disasters and
dictators. Digital text might also be effective
against jamming. This session will feature
recorded examples of digital text via shortwave,
but the decoding will be done live on the PC in
the room. (Obviously, plenty can go wrong here!)
1215 Luncheon (including In Memoriam and
progress updates from Prometheus, Ears to Our World and perhaps others.)
1345 Loop Antennas Reprised and CContinued
Jef Eichner. A partial recap of last yearâs
hugely popular program, including some new
information and experiments, then moving on to
broadband loops, relatives of the magnetic loop, loop sticks, etc..
1500 The Annual Pirate Forum George Ze
Zeller leads this merry (or not) band of
extra-legal radio enthusiasts in a discussion
about pertinent (or not) events and developments in the past year.
1615 Silennt Auction ends.
1630 Movie Matinee at Plymouth Meeting.
1830 Cocktail (Half) Hour
1900 Banquequet (Keynote Speaker tba)
2100 Raffle
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<mailto:[email protected]>[email protected]
http://montreal.kotalampi.com/mailman/listinfo/swlfest
To unsubscribe: Send an E-mail
to
<mailto:[email protected]>[email protected]?subject=unsubscribe,
or visit the URL shown above.
For more information on the Fest, visit:
<http://www.swlfest.com/>http://www.swlfest.com
http://swlfest.blogspot.com
_______________________________________________
Swlfest mailing list
[email protected]
http://montreal.kotalampi.com/mailman/listinfo/swlfest
To unsubscribe: Send an E-mail
to
[email protected]?subject=unsubscribe,
or visit the URL shown above.
For more information on the Fest, visit:
http://www.swlfest.com
http://swlfest.blogspot.com
_______________________________________________
Swlfest mailing list
[email protected]
http://montreal.kotalampi.com/mailman/listinfo/swlfest
To unsubscribe: Send an E-mail to
[email protected]?subject=unsubscribe, or visit the URL shown
above.
For more information on the Fest, visit:
http://www.swlfest.com
http://swlfest.blogspot.com
