brainwagon "There is much pleasure in useless knowledge." — Bertrand Russell

30Dec/090

DK3WN SatBlog » XW-1 SSTV

More fun on HO-68!

During a low elevation pass, Mike DK3WN and Henk, PA3GUO made the very first SSTV contact via HO68 – linear transponder. Images were transmitted between the two radio stations in Germany and The Netherlands. Signals were transmitted to HO-68, which was 1200km above earth and about 8000km distant from the radio amateur stations.

Check out the pictures!

via DK3WN SatBlog » XW-1 SSTV.

30Dec/090

Build Your Own 3D Scanner: Optical Triangulation for Beginners

I keep thinking that I should build one of these, but have never gotten around to it. Bookmarking this interesting link for future reference:

Build Your Own 3D Scanner: Optical Triangulation for Beginners.

30Dec/091

HO-68 in SSB mode

I don't really have the hardware to effectively transmit to satellites in linear transponder mode. To really make it straightforward, you probably would like to have a computer to handle the Doppler tracking and antenna pointing, and a full duplex SSB transmitter (or a pair of ordinary ones). That's more than I am willing to invest at the moment, but with my little FT-817, you can actually receive these birds pretty easily, using my ever present Arrow antenna and just tuning by hand. So, that's what I did this morning: here is my recording of HO-68. It begins with a bit of the CW beacon, then shows me tuning around to try to find SSB signals. Sometimes, the tracking is pretty good, but later in the recording, my next door neighbor began mowing his lawn and running a leaf blower, and it was hard to hear (I need to use my over the ear headphones instead of these earbuds I've used for FM passes). Anyway, here's the recording:

2009-12-30-HO68-SSB, recording by K6HX in CM87 using an FT-817 and hand tuning