[amsat-bb] Re: NO-44 and ISS

Bob Bruninga bruninga at usna.edu
Sat Apr 11 20:46:26 PDT 2009

> I live in CO and have not been able to hear 
> anything from these sats. I understand they 
> may be quiet right now but I'm wondering if 
> anyone in CO or surrounding states has been 
> receiving any data? I would love to get
> something working.

It is easy to see.  Each of these two satellites have an automated APRS web page where you can literally *see* the activity up to date.  You can see the last packet heard by anyone, and you can see who heard it.  And you can see whree they are.

For ISS, see www.ariss.net
For NO-44 see http://pcsat.aprs.org

Each packet heard is shown, sorted by how long ago it was heard.  If you click on the station, you can see what sat-gate heard it an injected it into the system.  The SATgate is the callsign immediately after the QAO or QAR construct.  You can then see where they are by entering their call into the http://map.findu.com/CALL

Looking at the ARISS page right now at 9:27 PM Mountain time, you can see that about 8 stations have been heard today (about 5 or 6 hours ago) and that those are the only ones that have been heard then since 9 days ago.  So it looks like you might be lucky.  This tells us that the crew on ISS did turn on packet mode about 6 hours ago, and 10 people got through.  ANd this is the first time it has been on in 9 days.

Now, click on KN6NS-1 for example, and you can see in his packet:

KN6NS-1>S3PQSX,RS0ISS-4*,WIDE3-3,qAS,KD8CAO-6:'-_l -/]ok

That he was digipeated by RS0ISS-4* (the ISS callsign) and his packet was heard by KD8CAO-6 and injected into the APRS internet where this web page then saw it and put it on this web page.  The ISS signal is strong.  It is black and white.  If it is ON, then you will hear it on ANY base station antenna.  When it is off, no one will hear it.

Now, it has been 5 hours since the last station heard, but this does not mean it is back off.  Just look at the orbit.  Where is ISS now and where has it been for the last 5 hours.  Maybe it has not been over any active ham country.  So it -could- still be on.

BUT on the other hand.  If you can -see- on your tracking program that the ISS has passed over the USA or Europe in the last few hours, and you do -not- see any packets on the web page, then it is safe to conclude that the system is presently off.

Similarly, you can look at http://pcsat.aprs.org

and see that about 8 statiosn were heard today,
7 a day ago and so on, on down.  But PCSAT (NO44) is not black and white:

1) it is totally dead in the dark
2) it is barely alive in the light
3) it is ONLY strong enough to complete a  1 second user packet relay usually when it passes right under the sun. 
4) and only in the northern hemisphere where the best solar panels face "up".
5) and it is 10 times weaker than ISS so you will only hear it if it is high in the sky at your location.
6) therefore the only successful stations are usually under the satellite about mid-day.  And there is a two  month or so cycle as to where that is occuring on any given day...
7) and these will not get to the web page, unless there is also a satgate in the footprint to relay it to the APRS internet and hence to that web page.

SO, those two web pages give you the global bird's eye view live as to what is happening with those birds.  sleuthing out this info can give you a good feel what is going on.

Good luck.
'At least now you know the ISS does work.  Or at least it did 5 hours ago today...

Bob, Wb4APR

>Dave Mynatt
>Program Director
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