ps: These were Not Local Re-Broadcast images. They were from ISS.
How can you Tell: For one thing Doppler. When ISS has AOS, the down link will be 3.3K higher in frequency. If you have a FM receiver with a discriminator meter (Rare item on new FM Junk) you tune the FM discriminator to center the frequency. And you will see 145.803.3 as the center FM frequency. When ISS is overhead, the Doppler will be zero for a second and the down-link will be 145.800. As ISS passes away, the Doppler will cause the frequency to drift lower until at LOS downlink will be 145.997
If you have tracking software and a beam, the AOL and LOS signals will match. I had an 83 degree pass over Boston today. Those passes are hard to track since the satellite only Rises until is over head (very little azimuth). Then once it passes your QTH, you need to switch the beams very fast 180 degrees in azimuth.
aaah the good old days of Mir/ISS.
wf1f
On 10/28/2018 1:23 PM, Greg D wrote:
Hi folks,
I let my radio and SSTV program run last night. Several passes, none super high, so my expectations were low. Also the whole downlink frequency thing. But, as I sift through the images and static of the night, I see about a half dozen partial pictures! Yea!
But, three of them, two from the 12:35z pass, and one from the 14:11z pass, have an overlay from MMSSTV calling "CQ SSTV"! Were they sent down from the ISS this way, or was someone locally rebroadcasting them (incorrectly)? The image from the 11:02z pass seemed fine, though I only go a part of it ("Curiosity on Mars"), as was the 15:49z pass.
Next pass, a low one, beginning in 4 minutes at 17:27z... Fingers crossed.
Greg KO6TH
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