Listening to the ISS repeater

It’s pretty easy to listen to the amateur radio repeater on the International Space Station (ISS) with a very modest set up. Transmitting and making contacts using the repeater is a little more complex, but not too much.

The ISS repeater downlink (what the repeater transmits on and what we listen to) is 437.800 MHz. Because the ISS is moving across the sky at a pretty good clip, the listening frequency needs to be changed as the ISS goes by to account for Doppler shift. At the start of the pass, because the ISS is moving toward you, the listening frequency needs to be a bit higher, 437.810 MHz. As the ISS goes past, it’s moving away from you so the listening frequency goes down. By the end of the pass, you’re listening at 437.790 MHz.

ISS Downlink frequencies

A table of frequencies to listen to for the ISS repeater downlink
Frequency (MHz)
Start of pass437.810
Mid pass437.800
End of pass437.790

If you program these frequencies into your radio’s memory, it’s easy to step through frequencies during the pass.

My set up is pretty simple. The radio is a Yaesu FTM-3207D, but probably any radio will work. The antenna is a simple dual band mag mount on a side panel from an old computer case that serves as a probably somewhat inadequate ground plane. All of it is about 2m above the ground on a shelf.

A dual band (2m/70cm) mag mount antenna on a metal sheet sitting on a shelf
Dual band mag mount antenna setup for listening to the ISS amateur radio repeater

It’s a pretty simple setup, and I’m kind of surprised it even works. Your mileage may vary depending on your local RF environment. My shack/office is full of electronics and can be a bit on the RF noisy side, but I have no problem hearing repeater activity during ISS passes.

I have the radio set to 437.810 MHz (start of the pass) and when the radio picks up the ISS repeater, there’s suddenly a bunch of activity on the radio. When reception gets static-y, I switch over to the next frequency.

This would probably work for listening to other satellites with FM repeaters, although I haven’t tried that yet.

NC QSO Party 2024 Results

Happened to notice that the results for the 2024 NC QSO Party were out.

W4BXC ended up with 58 QSOs, 38 counties, and 200 bonus points for a total of 4608 points. That put us in 11th spot out of 96 submissions in the SO-OUT-PH-LP (Single Op, OUT of state, PHone, Low Power) category. Not bad.

This year there were a total of 522 logs submitted, and 64352 QSOs.

Looking forward participating in to next year.

CQ WPX 2024 Log Check

CQ WPX log check results arrived in my email a little while ago. No busted calls!

************************** Summary ***************************

       6 Raw    QSO before checking (does not include duplicates or missing exchanges)
       6 Final  QSO after  checking reductions

      16 Raw    QSO points
      16 Final  QSO points

       6 Raw    mults
       6 Final  mults

      96 Raw    score
      96 Final  score

    0.0% error rate based on raw and final qso counts
    0.0% score reduction
      0  (0.0%) not in log
      0  (0.0%) incorrect calls
      0  (0.0%) incorrect exchanges
      0  (0.0%) missing exchanges
      0  (0.0%) duplicates removed
      0  (0.0%) calls unique to this log only (not removed)

********************** Results By Band ***********************

            Band   QSO   QPts  Mult

   Raw      160M     0      0     0
   Final    160M     0      0     0

   Raw       80M     0      0     0
   Final     80M     0      0     0

   Raw       40M     0      0     0
   Final     40M     0      0     0

   Raw       20M     0      0     0
   Final     20M     0      0     0

   Raw       15M     0      0     0
   Final     15M     0      0     0

   Raw       10M     6     16     6
   Final     10M     6     16     6

  Raw        All     6     16     6        96
  Final      All     6     16     6        96

************************ Multipliers *************************

  IO5   KP2   NP4   P49   PJ2   S55 

Portable operating and Hamsats

Added a couple new books (that are not ARRL Handbooks!) to the collection.

Portable Operating for Amateur Radio was one I’d been wanting to get for a few months now to support my portable operating ambitions, and I happened to find a copy on the shelves at a used bookstore. Seems like a pretty good book with some useful information for different styles of portable and mobile operating.

Front cover of Portable Operating for Amateur Radio by  Stuart Thomas KB1HQS.  The cover features a man kneeling on a mountain top summit holding a microphone connected to a radio on a metal frame backpack.

A copy of Amsats and Hamsats (an RSGB publication) also happened to be on the shelf too, so I thought I’d pick that one up too. Aside from listening to the ISS repeater when it goes overhead, I haven’t looked into doing much with amateur radio satellites yet but I’ve always thought it would be interesting and fun. This book seems like it’s got a decent collection of information in it.

The front cover of Amsats and Hamsats by Andrew Barron ZL3DW