New Satellite db Suggestion: CalPoly DAVE CP-7

According to this news report, the CalPoly cubesat DAVE (Damping and Vibrations Experiment) is scheduled to launch on Saturday on a Delta II rocket from Vandenberg Air Force Base.

Here’s a picture:

This spreadsheet by JE9PEL shows telemetry beacon as “437.150 MHz 9600bps FSK CW”

http://www.ne.jp/asahi/hamradio/je9pel/satslist.xls

I don’t know where to look for the preliminary tracking TLE, but I’m sure someone here knows :slight_smile:

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I’ve added CP7 (DAVE) in db (temp norad id 99995) and I’m going to add the two ELFIN and SurfSat that are in the same rocket too. Unfortunately haven’t found TLE yet.

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All satellited are added.

With the help of @cgbsat, who calculated some TLE based on some assumptions and on this document, I have added some observations on network.

Here are the satellites with their temporary NORAD IDs:
99992 SurfSat
99993 ELFIN-A
99994 ELFIN-B
99995 CP-7 (DAVE)

@cgbsat’s TLE:

1 74000U          18258.54305556  .00000000  00000-0  50000-4 0    00
2 74000  92.0000 249.0000 0000730 108.9500  20.0000 15.32788960    03
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I just saw this tweet, but I can’t find them:

I expected to find them here:
https://celestrak.com/NORAD/elements/tle-new.txt

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I created an account and logged in to celestrak and I think I found them:

1 43613U 18070A 18258.60318660 -.00000006 00000-0 00000+0 0 9993
2 43613 93.0220 249.5823 0009314 305.5615 157.2596 15.34667927 05
1 43614U 18070B 18258.66263174 -.00000007 00000-0 00000+0 0 9990
2 43614 93.0421 249.6384 0019532 301.5588 129.7408 15.36462002 16
1 43615U 18070C 18258.66277113 -.00000006 00000-0 00000+0 0 9998
2 43615 93.0192 249.5912 0011064 280.8151 151.3618 15.36143759 14
1 43616U 18070D 18258.66285850 -.00000007 00000-0 00000+0 0 9997
2 43616 93.0276 249.6128 0014394 291.4897 141.1132 15.36343853 17
1 43617U 18070E 18258.66288130 -.00000007 00000-0 00000+0 0 9992
2 43617 93.0368 249.6273 0017935 295.9046 136.7842 15.36584590 02

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Thanks, TLE for all of the sats are updated and also I’ve updated already scheduled observation with them.

By 90% in this observation we had decoded the first data from DAVE, but we need to confirm that it is indeed DAVE.

It looks like that it follows the TLE of DAVE (thanks to @cgbsat and @kerel for the plot):

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That does look good for DAVE. This really short observation looks promising for SurfSat, although the frequency might be off by 10kHz (I double checked the frequency coordination but it agrees with our db entry).

https://network.satnogs.org/observations/251323/

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About SurfSat, two more observations have similar signal at -10KHz:
https://network.satnogs.org/observations/251324
https://network.satnogs.org/observations/251374

As we don’t have decoded data, I think we should wait for a couple more to verify that this is SurfSat.

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We could add another transmitter that matches the correct frequency to see if we can gather some decodings.

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After some discussions on #cubesat channel, we learned that FCC regulations limit transmissions of cubesats at IARU coordinated frequencies.

So, in ELFINs case the beacon couldn’t be turned off so it transmits. We have also been requested to give more priority to ELFIN-B as it is only heard, while ELFIN-A was heard and commanded.

For SurfSat there was the ability to turn off their beacon, so this is why we haven’t got it yet. Maybe if there is a station near their ground station could get something.

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I have done some observation of ELFIN-B.
Observation 251749
Observation 251748
Observation 251747
There seem to be some sort of satellite signal around expected frequency, but I’m not sure if this is Elfin or some other satellite at simmilar orbit. If this is Elfin-B, then TLE seem to be a bit off and frequency may be off by some 4kHz.
Jed SQ2DK

Thanks, I didn’t see those. So in 251748 you can see horizontal lines of ELFIN-B in the middle and on the left edge half of the lines of ELFIN-A. Unfortunately no signal on the other two, the almost vertical lines, probably are from other satellites.

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In 251748, if you listen to the audio at the times of the horizontal lines (it is a shame that the waterfall scale is seconds while the audio scale is in minutes), you can hear the noise spectrum change, so this does seem to be a very weak signal.

I’ve opened an issue https://gitlab.com/librespacefoundation/satnogs/satnogs-network/issues/530 for fixing scales of waterfall and audio.

Indeed the reports say that ELFIN-B is weak, this is why we need to prioritize it in our observations.

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The issue with waterfall/audio time scale is fixed in dev (thx @kerel)… soon fix will be available in production too :slight_smile:

After request on irc/matrix we are going to share again the time between DAVE, ELFIN-A and ELFIN-B equally (instead of prioritize ELFIN0-B). About SurfSat as soon as we have info about when/if it transmits we will try to receive it.

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norad ids assignments: ELFIN-A --> 43617, ELFIN-B --> 43616, CP 7 (DAVE) --> 43615, SurfSat --> 43614 according to this tweet:

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