Working Satellites
Everyone could read via the RFDX Facebook that I had contact with an astronaut on the ISS.
A dream, a bucket list for many.
However, it is easier than you think to create this qsl.
It really is not that special, and certainly not difficult, to use the ISS repeater via your UHF/VHF set.
Ok, admittedly, it is of course special that an Astronaut takes the mike.
But using the ISS repeater is really easier than you think.
And I'm going to cover that for you here.
The ISS is equipped with a crossband repeater for ham radio amateurs.
This means that there is simply a repeater on board the ISS for us.
And we can simply use this with your 25w transceiver.
The frequency to operate is:
To transmit (UP): 145,990
To listen (Down): 437,800
The tone you must send is: 67
The status of the ISS repeater can be found here: https://www.ariss.org/current-status-of-iss-stations.html
If you have set this up on your set, you can call the ISS repeater.
And of course hope that someone responds back. These are generally other ground stations in Europe that you will hear and call to you.
And then of course you respond back.
You will hear: PD2TX the HA7CC JN97NL
So you quickly give the call of the opposing station and your own call with GRID, that's all!
You don't provide more information, because the ISS is hovering quickly over your location :), so you don't have much time for a QSO.
The above is an example of the ISS floating above the Netherlands...
But we can also very well extend this.
If you use 1 frequency, as I indicated above, you have about 3 minutes to make a qso.
That's short, and certainly too short to possibly reach an astronaut on the ISS.
So it is nice to extend this time.
And that's possible! Because we have the dopler effect.
This means that the approaching ISS station can be reached with a different frequency than when it is above you or when it is moving away from you.
You can then program the following frequencies into your set:
In this case ISS A is the upcoming ISS station (For England) ISS B in this case is the upcoming ISS station (Upper England) In this case, ISS C is the upcoming ISS station (Upper Netherlands) ISS D in this case is the upcoming ISS station (Over Germany) ISS E in this case is the upcoming ISS station (Upper Poland)
You can of course follow the tracking of the ISS live, which is of course necessary for it to work.
Here the link: https://pd2tx.com/iss-tracker-live
The circle you see around the ISS is the space you have to make contact.
In addition to setting it manually according to the example above, you can have it done automatically for some sets.
A nice software package is "SatPC32" link: https://www.dk1tb.de/indexeng.htm
This works great and is free to use.
You can also buy a license which I did, but it doesn't add anything extra.
It does require a bit of setup, but the website and YouTube are full of it.
What is important is that you use the menu > ? > Auxilary Files > Doppler.sqf
Just changes the following to:ISS,437800,145990,FM,FM,NOR,0,0,FM tone 67.0Hz,Cross band repeater
Because here the frequencies are 'twisted'.
I have already passed this on to the programmer, so it may have already been adjusted.
Have fun, make many QSOs, and who knows, maybe one day you'll hear "Welcome on Board"
'73 Nico 19RF1176/PD2TX
Oh before I forget..... In this case we talked about the ISS, but there are more than 30 other ham radio satellites.