ISS bounce

April 7th, 2013

Tonight Jan, PA3FXB and I tried, what we were discussing about for quite a while. There was a prediction of an ISS pass shortly after local midnight and both of us had no other appointments. So we agreed that Jan should make a transmission on 1296.300 MHz as soon the ISS became visible to him and tracking it as long as possible. My part was to monitor the pass of the International Space Station on my SDR. We used 3 m dishes on both ends and Jan had approximately 375 W in CW.

PA3FXB via ISS Beginning

PA3FXBs signal at the very right

Here is the result. Jan appeared with a relatively strong signal (on the very right), faded out and came back with weaker signal strength. I interpret it, that the first appearance was backscatter and the second was forward scatter, what has to be discussed. Doppler was extremely strong and more than 40 kHZ at the beginning.