[amsat-bb] Re: Video of indoor, ultra-cheap cubesat operations

Mark Vandewettering mvandewettering at gmail.com
Sat Jan 26 09:08:02 PST 2008


On Jan 26, 2008, at 4:59 AM, Bruce Robertson wrote:

> This morning I used the same setup to listen to a 2 deg. max elevation
> pass of LO-19. Its signal is stronger, of course, but it probably
> would be less well-suited to demonstration because it sends telemetry
> periodically, not continuously. It is easy to lose the signal in the
> doppler as the telemetry goes silent. However, with a practiced hand,
> familiar with the period of the LO-19 telemetry it is quite possible
> to record 559-ish copy from this bird without a preamp and with a
> directly-attached 1/4 wave vertical.
>
> I wonder if one could design a circularly-polarized antenna for 435
> MHz that directly attached to the BNC and could be supported by an
> FT-817...

Filed under the department of coincidences, I tried decoding the
LO-19 telemetry a couple of days ago.   The thing is: I don't have
anything except my trusty TH-D7A (FM only dual band HT).  I was
really just curious if I could hear it.  The answer is yes, and in fact,
it wasn't hard to decode the Morse that it sent (crude as my morse
skills are) by simply looking for the dots and dashes as changes
in the background noise.  If my decode of the telemetry was right,
it was putting out 1027 mw of TX power, which is art of what
made it really easy.

Recordings and decodes here:

http://brainwagon.org/?p=2729


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