08-09 - TELE-satellite International Magazine

All Satellites with a Fixed Dish
In the article there is presented a new concept
of a SAT-TV antenna with a superwideangle
sector of the feed scanning, the mirror
of spherical profile being immovable.
The angle sector of coverage reaches 140° which
permits to cover practically all the visible satellites.
The antenna aperture dimensions are 1.5 x 2.8 m.
The concept offered presents a special interest for
antennas of more than 3 m in diameter with large
mass which are difficult to rotate and position.
Low-Cost reception of weather satellites
Weather satellites use frequencies around
137MHz. To perfectly receive the data, a bandwidth
of 34 to 40kHz is required. A normal
radio scanner won’t do the job here. Some
modifications will need to be done as most
scanners have bandwidths of 15 or 90kHz.
The solution is DIY which is no problem as only
relatively low frequencies are involved. In 1994,
a project named HRX-137 started. It is a build-ityourself
receiver. Throughout the years, the quality
has been greatly improved. And the imagination of
amateur developers seems to have been unlimited,
making it almost a professional receiver. The basic
version with Scan control continuously searches
the 137Mhz and locks on to any weather satellite
signal it finds. Other signals are ignored.
During our tests, the following frequencies
were used:
NOAA 12 on 137.500MHz
NOAA 14 on 137.620MHz
NOAA 15 on 137.500 MHz
Meteor 3-5 on 137.300 MHz (will be
replaced with the new Okean)
Okean 4 (1-7) on 137.400 MHz
Sich-1 on 137.400 MHz
Resurs 0 (1-4) on 137.850 MHz
We asked TSI hardware guru Jan to build the
receiver and test it, all in one weekend. And
indeed on Monday morning the result was a
perfect receiver for the price of only 110 Euro.
On the front, 16 LEDs are in place to indicate
the frequency range between 137.0 and 138.0
MHz. It shows the scan procedure or the relative
frequency when locked on to a satellite.
Once upon a time, at King Arthurs throne, while the clown is doing his tricks, the magician
tells a story: »Many years from now fun and enjoyment will fall down from the skies.
Men and women will taste from it, and be silent and calm, leaving the ruler alone to rule.
Everyone will have a small box with buttons agore, ordering his or hers entertainment. This
box will be called remote, but this is hundreds of years from now.»
King Arthur: »Damn!«
Want More? Free Time Travel 10 Years Back:
Read Full Magazine TELE-satellite 07-08/1999 Here:
http://magazine.TELE-satellite.com/vintage/TELE-satellite-9908-deu-eng.pdf
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