SUN ECLIPSE 11th Aug. 1999
|My EME-site was just
within the total eclipse zone, so I let my autotracking
system make a sunnoise plot on 70cm. OE5EYM did the same
The 3dB beamwidth of my dish on 70cm is 4.4deg, OE5EYM´s dish has 1.2deg on 23cm with his 13m dish. Sunnoise was down 6dB on 70cm and 10dB on 23cm. Of course the deeper dip on 23cm is partly explained by not getting all the radiation of the corona because of the narrow mainlobe. But this cannot cause the difference of 4dB compared to 70cm. So I think, there must be less coronal energy radiated by the sun on 23cm. Our antennas are only a few kilometers apart from each other, so conditions at total eclipse were the same.
While my system made the measurement, I went to my home QTH which was in the center of the total zone. I picked up my family and had big luck as the weather improved. Back into the car, we were chasing a clear spot in the sky and could see the corona and Venus beside moon/sun for two minutes, sitting in darkness. The mountains far in the south were outside the total zone and covered with soft red/yellow light.
An impression we will never forget!
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