‰  NOW 10 WPM  ‰  TEXT IS FROM MARCH 2009 QST  PAGES 95, 96 AND 81  ‰

AND HARNESS THE EFFECT FOR VARIOUS APPLICATIONS, INCLUDING DECEPTION.  FOR
EXAMPLE, IT MAY BE POSSIBLE TO EXPLOIT THIS EFFECT TO CREATE A RADAR SYSTEM
THAT FOOLS OBSERVERS INTO BELIEVING THAT THE RADAR PULSE IS COMING FROM A
GIVEN DIRECTION WHEN IT IS ACTUALLY COMI
‰  FROM PAGE 81  ‰
D KP2/AA1BU 187,052 B B LU1FDU 231,085 A B CS95BD 15,196 B C Europe WP3GW
COPY 12 DB UNDER THE NOISE.  IT WORKS JUST FINE UNDER FM LIMITING AND I
THINK THAT IS BECAUSE THE DSP FILTERING IN THE SOFTWARE IS NARROWING THE
AUDIO NOISE WINDOW.  DOMINOEX IS ALSO A FREQUENCY SHIFT MODE, SO IT HAS
FEWER PROBLEMS WITH MULTIPATH AND ATMOSPHERIC DOPPLER DISTURBANCE COMPARED
TO PSK31 OR PSK63, AND YET IT OPERATES AT THE SAME EFFECTIVE SPEED 50 WPM
AS PSK31.  THE SIGNIFICANCE OF ALL OF THIS IS THAT THOSE THOUSANDS AND
THOUSANDS OF HAMS WHO HAVE ONLY FM TRANSCEIVERS WITH NO SSB CAPABILITY, CAN
NOW JOIN SSB OPERATORS IN CHASING 2 METER DX AND WORKING TOWARD THEIR VHF/
UHF CENTURY CLUB AWARDS.  THE KEY IS USING HORIZONTAL GAIN ANTENNAS AND AS
MUCH POWER AS THEY CAN MUSTER.  MANY MODERN FM RIGS WILL GENERATE AT LEAST
50 W OUTPUT.  THATS ADEQUATE FOR DOMINOEX 8.  ADD AN AMPLIFIER TO RUN 100 W
AND THEY WILL DO EVEN BETTER.  BEFORE THIS ARTICLE WENT TO PRESS, MORE
EXPERIMENTS WERE DONE WITH 4 BAUD DOMINOEX AND SKIP NOTES EVEN BETTER
PERFORMANCE.  YOULL FIND DOMINOEX AS PART OF THE FREE FLDIGI SOFTWARE FOR
‰  FROM PAGE 81  ‰
RX0AW 503,004 C B KG6DX 327,960 C C North America 5H3EE 22,176 A C RX9SA
1,673,606 C C ZL2BR 252,963 C C VP9/K9ZO 456,720 A B D4C 2,595,486 B B UP4L

ECLECTIC TECHNOLOGY DIGITAL WEAK SIGNAL FM?  WB8IMY SKIP TELLER, KH6TY, HAS
BEEN INVOLVED IN DEVELOPMENT WORK ON THE NARROW BAND EMERGENCY MESSAGING
SYSTEM NBEMS.  IF YOU DIDNT CATCH MY PREVIOUS COLUMN ON THE TOPIC, YOU CAN
LEARN MORE ABOUT NBEMS AT WWW. W1HKJ. COM/NBEMS/.  THE SHORT AND SWEET OF
NBEMS IS THAT IT IS A SUITE OF WINDOWS SOUND CARD PROGRAMS THAT ALLOW HAMS
TO EXCHANGE DIGITAL INFORMATION USING ERROR FREE ARQ AUTOMATIC REPEAT
REQUEST FORMATS.  IT IS DESIGNED FOR RAPID DEPLOYMENT DURING EMERGENCIES
AND OTHER PUBLIC SERVICE EVENTS.  SOMETHING VERY INTERESTING EMERGED DURING
SKIPS RECENT NBEMS EXPERIMENTS.  WHILE USING A DIGITAL SOUND CARD MODE
KNOWN AS DOMINOEX, HE DECIDED TO RUN SOME TESTS WITH ORDINARY 2 METER FM
MOBILE RIGS AND HORIZONTALLY POLARIZED GAIN ANTENNAS.  TO SKIPS AMAZEMENT,
HE DISCOVERED THAT HE WAS ABLE TO USE THE 8 BAUD FORM OF DOMINOEX DOMINOEX
8 TO SEND AND RECEIVE TEXT AT SIGNAL LEVELS SIGNIFICANTLY LOWER THAN WHAT
IS COMMONLY EXPERIENCED USING SSB.  OUR TESTS HAVE CONSISTENTLY SHOWN THAT
YOU CAN GET 100 COPY USING DOMINOEX 8 WHEN SSB PHONE CAN NO LONGER BE
UNDERSTOOD, SKIP SAID.  THE REASON THIS WORKS IS BECAUSE DOMINOEX 8 CAN
‰  FROM PAGE 81  ‰
RW0AJ 142,956 C A RU1A 2,741,640 D VK2AYD 82,816 C B EA8ANE 3,488 A B
RA9FTM 897,024 C B HG6N 2,630,034 D VK2GR 24,752 C B ZD8Z 3,040,433 A C
RA9AP 788,256 C B OG0A 2,183,134 D VK6AA 492,356 C C CT95EE 218,364 A C
‰  END OF 40 WPM TEXT  ‰  QST DE W1AW  ƒ