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+--- Thread: Moon Orbiter (/thread-586.html)
Moon Orbiter - VK2FAK - 20-06-2018
Hi All..
Has anyone had an attempt to get a decode of the Moon orbiter in JT4g or Gmsk as yet..?
John
RE: Moon Orbiter - VK2FAK - 24-06-2018
Hi all...
Oh my, the Moon flies almost overhead, and nobody here with a 70cm array bothers to look up to see if they can decode a signal last night......
RE: Moon Orbiter - VK4ADC - 24-06-2018
And many of the people who have fairly high performance 70cm stations were probably providing contest numbers in the Winter VHF/UHF Field Day last night instead of staring at the moon... At least I hope they were.
I don't know about others but my 432 yagi points at the horizon and not at the sky - and has no option to orient it upwards either unless I tilt the tower onto its side as if to do maintenance on it.
I'm guessing those unpointable-yagi matters might attenuate the already very weak signals from the moon orbiter assuming I was interested in trying ?
RE: Moon Orbiter - VK2ZIW - 24-06-2018
Have a look at the Link Budget.
http://lilacsat.hit.edu.cn/wp/?page_id=676
There they have a 20db gain antenna.
I'm flat out getting 16db, 10db at the moment....
Alan VK2ZIW
RE: Moon Orbiter - VK2FAK - 25-06-2018
Hi All,,
Yes fully understand, my attention was going towards the EME type set-ups which we seem to have a few in the country. I am also in the situation of not having an antenna with enough gain, does just fine for normal LEO sats, but not in this case. But as the Orbiter will be operational for at least 12mths (expected) I will attempt to make something. And it seems some people are getting a signal with smaller antenna
RE: Moon Orbiter - VK2KRR - 25-06-2018
I need more info on this if possible? I have quite a lot of gain on 70cm (and relatively few stations or beacons in terrestrial form). I can only access the moon from about 10 deg or so above the western horizon.
RE: Moon Orbiter - VK1JA - 25-06-2018
I'm willing to give this a try, not sure how I'd go, but I'll give it a go.
Me being slack, is there a site that has frequency, mode used etc?
I'm guessing we point at the moon?
RE: Moon Orbiter - VK2KRR - 25-06-2018
I just tried a search and could not see anything about JT modes on a moon orbiting satellite.
RE: Moon Orbiter - VK2FAK - 25-06-2018
Hi All..
here is some info..
Two linear polarization antennas are mounted along and normal to the flight direction. The downlinks for DSLWP-A1 are 435.425 MHz and 436.425 MHz while downlinks for DSLWP-A2 are 435.400 MHz and 436.400 MHz using 10K0F1DCN or 10K0F1DEN. Will use 250/500 bps GMSK with turbo code or JT4G. Uplinks are reported to be in the 144 MHz band.
There is a schedule. Coming days I will need to ask for.
Before decoding, it would be nice just to see a signal or two.
John
RE: Moon Orbiter - VK1JA - 25-06-2018
https://amsat-uk.org/2018/05/19/dslwp-satellites-lunar-orbit/ has some details, but there's no mention of JT modes, only GMSK.
'Satellite A will transmit 500 baud GMSK with 1/4 turbo code on 435.425 MHz and 250 baud GMSK with 1/2 turbo code and precoder on 436.425 MHz, and satellite B will transmit 500 baud GMSK with 1/4 turbo code on 435.400 MHz and 250 baud GMSK with 1/2 turbo code and precoder on 436.400 MHz, in every 5 minutes by default. Each transmission will last about 16 seconds.' and it links to a Linux software to decode the data.
BUT - http://lilacsat.hit.edu.cn/wp/?page_id=676 does mention a JT65B mode beacon.
BUT BUT - there seems to be conflicting information floating around because here - http://destevez.net/2018/06/dslwp-b-detected-with-7-element-yagi/ it mentions JT4G !!
I'm trying to find clear information - frequency/mode/transmission type but I'm having problems.
So the questions are:
Frequency - 435.425 MHz, 436.425 MHz, 435.400 MHz or 436.400 MHz ??
Mode - JT65B, JT4G or GMSK ??
Transmission mode - USB, FM ??
Schedule that the sats aren't behind the moon ??
Some more info on Twitter as well, this might be more useful for current status - https://twitter.com/bg2bhc
RE: Moon Orbiter - VK2FAK - 25-06-2018
Hi all..
I think the JT65 was mention while testing, but its JT4G.
USB. your looking at 435.400 JT4G 436.400 GMSK
The schedule, not sure the reason, but follow that twitter and he will tell the next time. he gives pretty quick responses if you want to tweet a question.
The next tx I think I read would be on the weekend, but keep eyes open if you want to try
Last schedule were in 2hr segments over a few days
RE: Moon Orbiter - VK4ADC - 25-06-2018
Part of the detail posted above needs to be highlighted for others following the thread and interested in trying to 'hear' (
) it....Some more info on Twitter as well, this might be more useful for current status -
https://twitter.com/bg2bhc
RE: Moon Orbiter - VK2FAK - 26-06-2018
Hi all,
details and example of people and equipment that have had some success......some early before in moon orbit.
http://lilacsat.hit.edu.cn/wp/?page_id=844
RE: Moon Orbiter - VK2FAK - 29-06-2018
Hi All...
The new tx times for the satellite..
DSLWP-B UHF test,
30 Jun 00:00 to 30 Jun 02:00,
30 Jun 05:00 to 30 Jun 07:00,
30 Jun 16:00 to 30 Jun 18:00,
1 Jul 07:00 to 1 Jul 09:00,
all time in UTC
Looks like the 30 Jun 16:00 UTC is for us.
RE: Moon Orbiter - VK1JA - 29-06-2018
I'll be listening in at 2am on Sunday morning.... Or should I say, I'll leave the radio on while I sleep !
RE: Moon Orbiter - VK2FAK - 29-06-2018
hi all...
Yes it certainly is not an ideal time, has been better the last few times.
Seems a bit crazy, as not good for the Ground Station either
RE: Moon Orbiter - VK2KRR - 29-06-2018
Thats no good for anyone who doesnt have elevation control (such as myself). Moonset will be sometime around sunrise I think.
RE: Moon Orbiter - VK2FAK - 01-07-2018
hi all..
Any luck, or just to damn cold and the warm bed was a much better option....lol
RE: Moon Orbiter - VK1JA - 01-07-2018
I didnt have any decodes this morning, so nothing from me.