Digital-ATV at HAM RADIO 2001
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The digital Amateur Television test provided by a group around
DJ8DW from Wuppertal university at the HAM RADIO 2001 fair in
Friedrichshafen, Germany, was built up over a 9 km distance
from the "Elektronikschule Tettnang" building to hall 6. On 
434 MHz plus/minus 1 MHz 80 watt power output were used in 
GMSK modulation and a fourfold 11-el. yagi group at each 
location.

On Friday morning the video and sound transmission in MPEG2
quality was successful at times, but strong inband short-time
carriers interrupted it more and more. So an originally planned
long path test over 26 km from Austria was cancelled.

Several TV monitors at the combined stand of DARC public relations
and AGAF e.V. were showing all three days long, how well an
undisturbed 3. generation digital-ATV link can work. On 1255 MHz
plus/minus 3 MHz 10 mWatt in QPSK modulation with FEC (forward 
error correction) provided excellent video and sound quality,
received by a cheap digital satellite TV settop-box in MPEG2.
After intentionally interrupting the path an error message from
the settop-box menue appeared on a black TV screen, but after 
realignment the live picture was back with some delay.

Uwe Kraus, DJ8DW, will soon present a detailed description of 
3. generation DATV which is designed to enable experienced
TV amateurs to use the new single chip MPEG2 coders and decoders 
from Fujitsu and a universal modulator for GMSK, QPSK or 8VSB.

web info: www.darc.de/g/datv/datvindex.html

Klaus, DL4KCK
AGAF e.V.