Posted in: ISS

ISS FM Phone Repeater

If you are interested in making a contact over the ISS FM Phone repeater. I have successfully made four contacts so far. I am by no way an expert on working the birds, but this is what has worked for me recently on the ISS FM phone repeater.

Antenna: I am using my normal J-Pole on the eve of my house. Certainly a handheld dual band yagi would work much better, but I do not yet have the hand coordination to get that to work yet.

Voice Recorder: Not required. But I use the apple voice memo app on my iPhone, and place it next to the speaker. I like to record the audio of the pass to listen to after.

Pen & Paper: I write down all call signs heard during the pass as I hear them. That way I am ready to call the most recent one back when there is a pause in the contacts. It is like breaking into a pile up on a contest, but there is not one main station. I try to call one that sounds loud and clear to me.

Tracking software: There are many out there which work well. I prefer to use an iPhone app called SATSAT for upcoming times. It works very well. I also use for timetables. And I like to have this one up full screen to see the footprint during the pass Link: Live Space Station Tracking Map | Spot The Station | NASA

Radio: I do not have a 9700, or expensive satellite radio which can auto adjust for Doppler. I am just using my anytone dual band radio. I have programed five channels into my radio. This makes it easier to manage during the 10 minute pass.

All Channels us a TX PL Tone of 67.0. The UHF is most affected by the Doppler effect. I turn the squelch off. The repeater will break the squelch if turned on, but I find it easier with squelch off. Channels below. Start on channel one. Then move to channel, two, three, four, and finally five, throughout the ten minutes the ISS is passing. This will help account for the UHF Doppler effect.

CH RX Freq TX Freq Decode Encode

1 437.81000 145.99000 OFF 67.0

2 437.80500 145.99000 OFF 67.0

3 437.80000 145.99000 OFF 67.0

4 437.79500 145.99000 OFF 67.0

5 437.79000 145.99000 OFF 67.0

If you don’t hear the ISS repeater, there is no sense in transmitting, because it won’t hear you.

If you get this today before 8:11 am, there is a good pass going right overhead beginning at 8:11 am ET this morning.


Matthew KO4DJG