Quoting Bruce Robertson <ve9...@gmail.com>:
On Sat, Aug 13, 2011 at 7:07 PM, Phil Karn <k...@philkarn.net> wrote:
On 8/10/11 8:24 PM, Tom Azlin N4ZPT wrote:
I have a Fun Cube Dongle so I would Phil. Thanks and 73, Tom n4zpt
Okay, everybody make and keep your wideband I/Q recordings and I'll work
on an enhancement to my demodulation/decoding software to process them.
It may not run in real time on slower machines because of the need to
search a wider frequency range, but this won't matter if it can work on
a recording.
I can probably speed things up by including an orbit model in the modem
to predict Doppler open-loop, but this will take time to implement and
it will still be vulnerable to small errors in the elements and/or your
clock, especially around closest approach. So record the date and time
of your recordings and the current eleset at that time.
For those who have not noted this feature, HDSDR will open a recording
scheduler if you right click on the 'record' button. It saves files
with UTC time appended. The tricky part is that you have to set the
scheduler manually in local time.
I've been thinking it would be a nifty hack to make a FCD recorder for
a set of satellites using a very small computer, like the BeagleBoard.
It seems to me that a daily cron job with 'Predict' would just about
do what was necessary, especially now that we have a commandline tool
for the FCD. The only part that would take some fiddling would be
piping the USB sound card into a file with the proper headers for
HDSDR.
73, Bruce VE9QRP
I have to agree that HDSDR's recording scheduler is a really neat
feature. However, two improvements that I believe can make this even
better will be:
1. Although HDSDR can 'start' the receiving based on the start time of
a scheduler record, it only stops the recording at the end time of the
scheduler. It does not 'stop' the receiving - which will be good to
save CPU resources if the SDR is used in an automated unattended
satellite tracking station that has the PC shared with other stuff.
2. The need to set the scheduler manually could be eliminated if HDSDR
can make use of DDE output of satellite tracking software. For
example, in my station I use WISP + WISPDDE for antenna tracking while
the FCD is controlled by DK3WN's FCD control software.
If HDSDR could use the DDE output of WISP, it can start recording when
a satellite name appears, and stop when '*** NO Satellite ***' appears.
These are just some of my thoughts to make automatic unattended
reception easier, but I must say that DK3WN's FCD control + HDSDR are
really great pieces of software. Thank you to all those involved in
their development :)
73, Sion, 9M2CQC
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