Space Station Repeater ACTIVE Dec. 27-31/05

[VO1ONE]

For the first time in over 4 months, ISS's repeater will be turned on for a period of 3+ days to be used worldwide! The ISS in repeater mode is the easiest "satellite" to work. Operation will be possible with a standard dual band mobile radio with your standard run of the mill dual band magmount. Dual band HT's, especially those with the quarter wave rubber ducks should have no problems, either. Omni antennas will do just fine and you'll probably get full scale signals from them. I expect there'll be a LOT of activity due to the short period it will be on (and the rare occaision that it's actually turned on), the possibility of the astronauts/cosmonauts coming on to talk, and the ease of working this "satellite" repeater. Here's the write-up from www.issfanclub.com

As part of the Space Patrol special event activities, the Russians have submitted a request to place the Kenwood radio into repeater mode beginning some time on Dec 27 and operating until 0912 UTC on Dec 31 when Exp 12 Commander Bill McArthur will be speaking to Boy Scouts in Thailand.

It is anticipated that this request will be approved and that the radio will be available for amateur radio operators world wide during the 3+ days of operation.

The crew may also join in at anytime so be prepared to talk to them if they call. The worldwide downlink is 145.80 MHz, and the uplink is 437.80 MHz.
All frequencies are subject to Doppler shift. This link:
http://www.amsat.org/amsat/ariss/news/ISS_frequencies_and_Doppler_correction.rtf
on the ARISS website has a memory programming chart for dealing with the Doppler when using ISS in crossband repeater mode .

Special thanks to the PCSAT2 team for their coordination efforts to make this a possibility

Kenneth - N5VHO
ISS Ham Project Engineer

 

[KE4EST]

Thanks for posting this. I was wondering when it coming back up.

 

[VO1ONE]

I'm looking forward to it. Maybe I'll work you on one of our mutual passes! The reason why it is off so much is because it interferes with PCSAT2. The repeater transmits on 2 meters and PCSAT2 receives on 2 meters and since they are so close (in proximity and frequency) the repeater desenses PCSAT2. Here's a post from WB4APR, PCSAT2's command station explaining the predicament:

"Its a long story, but the answer is because of PCSAT2.
PCSAT2 was supposed to have been activated on ISS
in July 2003 and be FINISHED by Jully 2004. At that
time the Crossband repeater was not yet on board
and so to avoid any interference with 2 meter school
contacts PCSAT2 was designed with 2m uplinks and UHF
downlinks.

Problem is that Shuttle accident and 2 years of delays
caused PCSAT2 to actually arrive on ISS 2 years later
after the Kenwood did. But the Kenwood was designed
(as we hope all future payloads would be designed to
avoid these kinds of problems) to have UHF uplinks
and 2m downlinks.

So now if The Kenwood is activated with FM repeater
with 2m downlink, it will be on all-the-time and will
block any/all 2m uplinks and commanding to PCSAT2
and other payloads. The only alternative is to
operate the FM repeater in reverse, that is with
2m uplink and UHF downlink while PCSAT2 is still
attached (another 7 months). But that takes
dozens of keyboard steps to set up by the crew
and has such a potential to get missconfigured
especially since it would have to be done each time
after each school contact, that it appears to be just
too risky."

 

[VO1ONE]

I made a few contacts on the ISS repeater including one with G6CRV, but over the continents it is very difficult to get in with all the QRM. Only the big guns seem to be getting through. However, when it's over the ocean, I have no problem getting in with 1 watt. People need to adjust for doppler, listen and if they're not getting through, stop transmitting; don't hold the key for a minute. The ISS repeater's squelch is set pretty high so if the slightest signal is QRMing another, then it shuts off. The audio is pretty low. Don't overdrive your audio to compensate for it. Some have said that it will shut down if you do, although I've never experienced that myself. I'd say that'd have to do more with being off frequency due to doppler. Still a couple days left and the crew has been active at times on the repeater so give it a try. Good luck!

 

[KE4EST]

I have tried with no success yet.....will keep trying

 

[VO1ONE]

I have tried with no success yet.....will keep trying

Were you able to hear it, though?

 

[KE4EST]

Oh yes I have heard it on several passes, and just tonight one of the ones on board said it was going to stay on longer than the 31st. I would like to verify that, so we can start a new thread on it.

 

[g6crv]

I made a few contacts on the ISS repeater including one with G6CRV, but over the continents it is very difficult to get in with all the QRM. Only the big guns seem to be getting through. However, when it's over the ocean, I have no problem getting in with 1 watt. People need to adjust for doppler, listen and if they're not getting through, stop transmitting; don't hold the key for a minute. The ISS repeater's squelch is set pretty high so if the slightest signal is QRMing another, then it shuts off. The audio is pretty low. Don't overdrive your audio to compensate for it. Some have said that it will shut down if you do, although I've never experienced that myself. I'd say that'd have to do more with being off frequency due to doppler. Still a couple days left and the crew has been active at times on the repeater so give it a try. Good luck!

It is a problem with some stations using rigs with no duplex and no doppler shift control. At least if you have a rig like the Yaesu FT847 you can monitor your own signal through the ISS repeater. I use satscape to control doppler.
I am in the fortunate position to live on the west coast of UK and have a fairly unobstructed take off to the west (right on the coast here), so I can work through the ISS as it comes up over the horizon.
Many thanks for the contact on 28 Dec , I did hear you on 27 Dec also, but I left it too late to call you and it had gone below your horizon. I did listen for you on other passes when the ISS would be in range of New Foundland and West coast UK but no joy. Only a few of the passes are any good for cross pond contacts.
Dave G6CRV

 

[VO1ONE]

It is a problem with some stations using rigs with no duplex and no doppler shift control. At least if you have a rig like the Yaesu FT847 you can monitor your own signal through the ISS repeater. I use satscape to control doppler.
I am in the fortunate position to live on the west coast of UK and have a fairly unobstructed take off to the west (right on the coast here), so I can work through the ISS as it comes up over the horizon.
Many thanks for the contact on 28 Dec , I did hear you on 27 Dec also, but I left it too late to call you and it had gone below your horizon. I did listen for you on other passes when the ISS would be in range of New Foundland and West coast UK but no joy. Only a few of the passes are any good for cross pond contacts.
Dave G6CRV

Yes, I agree, although I do think some with full duplex are at fault as well. When they hear that they aren't getting through, they hold down the key until they can hear themselves. They don't realise that they are just adding to the QRM by doing that. Doppler is a big problem too. I think many don't realise that you have to adjust opposite of what you do when you are receiving the downlink on a satellite such as AO-51. It is easy to set up on any radio just by setting up separate memory channels for the different portions of the pass. Most will let you get down to 5kHz steps so you can start 10kHz under, then 5kHz, on frequency, 5 up, then ending at 10 up. The RX frequency for all of those would be the same of course, unless your radio has 1kHz steps. FM capture effect is usually good enough to compensate for the small amount of doppler experienced at 2m. Now if you have a satellite rig and a computer interface, you can have both right exactly down to the hertz automatically ;-) Of course, with the ISS repeater only being on for a few days during a time where a lot of people have time off from work doesn't help either. If the ISS repeater wasn't such a novelty it'd make it easier with more times of less activity.

Thanks also for our QSO. I wasn't on other passes because I was on holidays in Florida ;-) Took the HT with me, but was a little out of footprint for a UK mutual pass hi hi! Maybe I'll hear you on AO-51, SO-50 or AO-27 sometime. Footprint is much larger on those. Could manage a QSO longer than 2 sentences then hi hi!

73,
Mark VO1ONE