Ham radio repeaters
I have an old Yaesu I haven't touched for 10 years. Wondering whether it is worth the effort to dust it off. Have any ham operators out there had any success at all raising up contacts off repeaters...
Forum Discussion
John,
For one of the "NASA" questions the "correct" answer was wrong.
The question was "When is the best time to work EME?
The "Official correct" answer was "during a full moon".
It turns out that is one of the worst times because of the sun noise reflected from the moon.
The real best time is when the moon is about 15 to 30 degrees from the Sun and the sun is in one of the nulls of your antenna.
In the 1980s I worked 79 countries on 432 EME ...
1500 Watts PEP out of the transmitter
16 sixteen element Yagi-Udas on top of a 40 ft tower with an Az-El mount controlled by a TRS-80 Model One computer.
Beam width was ~1° and since the moon takes up 1/2° of arc in the sky, aiming had to be pretty accurate - remember the moon is moving at ~15° per hour. Compare this with hitting a running rabbit in the back of the head with a .22 rifle at 100 ft.
If you want to do the math, the ERP was ~500,000 Watts.
For one of the "NASA" questions the "correct" answer was wrong.
The question was "When is the best time to work EME?
The "Official correct" answer was "during a full moon".
It turns out that is one of the worst times because of the sun noise reflected from the moon.
The real best time is when the moon is about 15 to 30 degrees from the Sun and the sun is in one of the nulls of your antenna.
In the 1980s I worked 79 countries on 432 EME ...
1500 Watts PEP out of the transmitter
16 sixteen element Yagi-Udas on top of a 40 ft tower with an Az-El mount controlled by a TRS-80 Model One computer.
Beam width was ~1° and since the moon takes up 1/2° of arc in the sky, aiming had to be pretty accurate - remember the moon is moving at ~15° per hour. Compare this with hitting a running rabbit in the back of the head with a .22 rifle at 100 ft.
If you want to do the math, the ERP was ~500,000 Watts.
