ISS digipeater

Discussion in 'Satellite and Space Communications' started by KE3LB, Dec 2, 2016.

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  1. WD9EWK

    WD9EWK Ham Member QRZ Page

    The frequency information listed in this post is for LilacSat-2, but it was launched with several other amateur satellites from China in September 2015. LilacSat-2 has been rarely activated in the past year or so, but was on this morning in its FM repeater mode.

    The Chinese satellite that is due to be deployed from the ISS is LilacSat-1.

    It is scheduled to have a 9600bps BPSK downlink on 436.510 MHz. According to BG2BHC via Twitter, this satellite is scheduled to be deployed from the ISS on 23 May at 0815 UTC. Once deployed, there is a 30-minute timer before the satellite's radio and antenna are activated. It appears this will not have any uplinks available for amateur use.

    As for ISS, it appears that basically nothing is coming from its packet digipeater. A couple of reports this morning of some bursts on 145.825 MHz; otherwise, silence.

  2. WD9EWK

    WD9EWK Ham Member QRZ Page

    Briefly. DK3WN said it stayed on for a couple of orbits, then the voltage dropped below 7.5 V which shuts off the 145.825 digipeater. Oh well...

  3. K3RLD

    K3RLD Ham Member QRZ Page

    could it be that the ISS crew have purposely de-rated or slowed the packet repeater somehow in order to ensure initial confirmation of the functioning of the cubesats? I imagine at some point they will be far enough away from the ISS that it won't be an issue?
  4. WD9EWK

    WD9EWK Ham Member QRZ Page

    Maybe. I suppose anything is possible. ARISS has been mostly silent on the recent issues. With many in ARISS heading to Dayton this weekend, maybe someone there can ask ARISS for an update on the ISS packet situation.

  5. K9JKM

    K9JKM Ham Member QRZ Page

    That's good to know ... I saw the "new" LilacSat info on an AMSAT-UK post which pretty much consisted of only a link to the Chinese page. That page sort-of, but not so-good google translates into "Engrish" ... er, English ... I wonder if their new post confuses the Lilacsats. I guess it will be a bonus digipeater next week if the new Lilacsat has a digipeater that most packet beacons won't access via split frequencies.

    73 de JoAnne K9JKM
  6. WD9EWK

    WD9EWK Ham Member QRZ Page


    Back from a few days in the east, between the Hamvention and operating from different locations in Indiana, Ohio, and Ontario. With NO-84's digipeater off, and relatively inconvenient ISS pass times for many, I was only able to work a pair of passes a night during 3 evenings - Friday 5/19 from the Indiana/Ohio state line 30 miles/50km west of Dayton, Saturday 5/20 from the EN70/EN80 grid boundary northeast of Dayton, and two locations in Ontario on Sunday 5/21 (one on the EN92/EN93 grid boundary in London ON, and the other in EN92 about 60km/40 miles southwest of London). I made ISS packet contacts from each location, and at least one contact on every pass attempted except for one. I tried to send messages to almost every other station I saw on all of these passes, in the hopes of logging some packet contacts while operating away from home. More about the messages and QSOs later...

    The Friday evening passes from the Indiana/Ohio state line were decent passes, operating from a parking lot at a fireworks shop at the border east of the I-70/US-40 interchange. The shop sits in Indiana, and almost all of its parking is in Ohio. Unfortunately, the first of the two passes was mostly stations beaconing as they always seem to do the closer you get to the US east coast. The later (mostly western) pass was slightly better, with two QSOs in the log. With these passes coming by at roughly 11.15pm and 12.45am local time, I get that there might not be many at the keyboards for these passes in the east. But so many beacons...

    Saturday evening at the EN70/EN80 grid line northeast of Dayton almost didn't happen, Thunderstorms were rolling through the area all night, but with breaks where I could work the two ISS pass along with SO-50. The first of the two passes had stations from the eastern USA, Mexico (XE3N-1), and Cuba (CM8NMN) on there. In fact, a beacon from CM8NMN had my call sign among the listing of stations heard down there. I was able to make one exchange on the first ISS pass, with NZ4D-6. Later, after another heavy bout of rain moved off just before midnight, another ISS pass. This was, by far, the most productive ISS pass I worked on this trip. Four QSOs!

    Sunday evening was interesting. The Hamvention wrapped up, and I decided to try my luck crossing into Canada at Detroit, and operating for the evening and Monday morning in Ontario. Canada has permitted its hams to use special prefixes this year to commemorate the country's 150th anniversary, so I exchanged the VA prefix in my Canadian call sign with CF, and worked packet as CF7EWK. For other satellites in FM and SSB, I used CF7EWK/3. AX.25 packet does not allow the "/" in a call sign, and I didn't want to use the SSID -3 which doesn't necessarily mean anything these days for packet operations.

    After checking into a hotel in Windsor, I drove up the 401 freeway to the city of London, about 200km away. On my way there, I stopped at two locations along the 401 to work other satellites in FM and SSB, then found a spot in London straddling the EN92/EN93 grid boundary. I worked a few SSB passes from this spot, then moved down the street (and slightly north of the grid boundary) to work EB1AO in Spain via FO-29, and then returned to the grid boundary for the first ISS pass of the evening.

    The first of the two passes came by just after 11pm local time. Eleven other stations were seen on the pass, even as far away as Colorado, but a QSO was made with only one of them (WN9Q, in Wisconsin). Even with more time to work the stations closer to the US east coast, a QSO was hard to come by. Lots of beacons, and - probably - lots of unattended stations...

    For the next ISS pass, I departed London, and began my drive back to the hotel in Windsor. I made it about 60km/40 miles, and pulled off at an exit to find a spot to work the ISS and an SO-50 pass. I saw 6 other stations on this pass, again as far west as Colorado, but only one QSO (W0JW in Iowa). One QSO is better than none, and from some of the beacons I could see there had been other stations on as far west as Arizona and Nevada that dropped out of the footprint just as I was coming into it. Although disappointed at the tiny number of packet QSOs in Ontario compared to the number of stations heard, two QSOs are better than zero QSOs. The FM and SSB satellites made up for the low number of packet QSOs.

    I was able to work an SO-50 pass on Monday (5/22) morning on the edge of Windsor, which was the last satellite pass I worked from Canada and during this trip. No ISS from there, as it had already gone by during the night, and I needed to get some sleep before the drive across the river through US Customs in Detroit and then to Indianapolis for my flight home.

    It's always fun to work satellites when on the road. My portable setup used at home is basically the same as what I use away from home, including for packet via ISS and NO-84. AMSAT had a nice station outside one building at the Hamvention, but with the evening/early morning ISS passes and no NO-84, the W3ZM call sign wasn't heard on the ISS passes. All of my QSOs have been uploaded to Logbook of the World, and I'll send cards to anyone who worked me that e-mails me the QSO details.

  7. K3RLD

    K3RLD Ham Member QRZ Page

    Well, it's been a while since I was on the digipeater, so I gave it a whirl tonight. Some observations:

    1) Didn't seem to be bombed with beacons. There were 5 or 6 stations active (including me), but I think I was the only live operator. But I think all or most messages and beacons were digipeated (not a single confirmation on, but my D710 decoded a bunch of "my message" and "my position" packets). So not bad, I think. Lack of live operators is probably due to the start of the long weekend.

    2) Attempted sending a message to "TWITR", but it either wasn't digipeated or wasn't igated (I believe it to be the latter, as I believe that was one of the "my message" acknowledgements I got.

    3) My igate got 4 packets! this was a 30 deg max pass:

    20170527002320 : AC2KU-1]SYRT7S,RS0ISS*,qAO,K3RLD-10:'f:-l K\]=
    20170527002319 : RS0ISS]CQ,qAO,K3RLD-10:]ARISS - International Space Station
    20170527002225 : K4EKB]CQ,RS0ISS*,qAO,K3RLD-10:k4ekb - greetings from Virginia Beach - FM16xs
    20170527002214 : K1WY]TQTU7T,RS0ISS*,RS0ISS,qAO,K3RLD-10:'dGRl -/]K1WY FN31ps
    AD5KO likes this.
  8. K3RLD

    K3RLD Ham Member QRZ Page

    Again, 5 operators on tonights 01:10z 30 deg pass (visible pass.... easy to aim at!). Pretty laid back. One "ack", but seems to be automated. :(

    Again, however, NONE of my packets (easily 4 or 5 that were digipeated) show up on My igate didn't collect any satellite packets (only my terrestrial uplink packets). Seems like it only really likes north eastern passes (the house is to the south west).
  9. WD9EWK

    WD9EWK Ham Member QRZ Page

    If you had 5 live operators on that pass, that's great! I wasn't that lucky last weekend, on any of the eastern passes I worked from Indiana, Ohio, or Ontario. On passes that went to my west out there, I sometimes did better.

    Are you using the same call sign on your gateway as you are using on RF to the ISS? I thought that the APRS-IS system won't let you gate traffic from the same call sign as the gateway receiving you. If another gateway is picking you up, that gateway is permitted to pass your packets to the Internet.

  10. K3RLD

    K3RLD Ham Member QRZ Page

    Pretty sure that those 5 "operators" were actually just "automatic stations". Should've probably used "quotes" around operators. But there was certainly plenty of "airtime" to sneak packets in.

    As for the APRS-IS system, I am using "K3RLD-1" for my sat-ops, and my Igate is "K3RLD-10". If it makes that determination solely on the call sign (not the SSID), then that explains that. I just assumed that the SSID allowed the IS system to understand that there were two different "calls".

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