Satellite QSO

For anyone wanting to try their hand at a satellite QSO there is a new LEO Sat up and activated (November 2017) which is fairly easy to work: AO-91 (43017, FOX-1B)

This past week I made contact with WC7V in Montana while walking on a beach near Tofino. I used my FT1XDR with a Diamond SRH77CA dual band whip.  I made a contact from my yard a few days earlier but sadly forgot the callsign of the station by the time I found a working pen.  I now have a voice recording app which I keep running on my phone during a pass. This makes logging easier as I do not have to fiddle with writing anything down or remembering info while portable. Sitting at a desk might be different.

Passes are only a few minutes and the Sat can be busy so contacts are brief. Exchanges consist of your call followed by the first four digits of your maidenhead grid. A useful Android app for determining your grid is ‘Easy QTH Locator’.  My grid here in Little Qualicum, and most of central Vancouver Island, is CN79. So for me it is simply  “VE7VJ CN79”. You do not call CQ.  It is a good idea to listen to several passes before jumping in.

To track passes I’ve been using the “OSCAR” app for Android (free) which can show passes several days ahead. I look for one that will be high in the sky. The pass for the QSO above peaked at around 80 degrees.

NOTE: the tracking apps/sites can be persnickety when it comes to searching. Some will find “AO-91’ but not ‘AO91’. If you are having trouble try the NORAD ID:  43017

The frequencies for AO-91 are: uplink of 435.250 MHz (67.0 Hz CTCSS) and a downlink of 145.960 MHz.   Receive can be left at 145.960 but the xmit must be set as the table below to allow for the Doppler effect. I have only programmed the Approach, TCA and Departure.  You may have to move your handy antenna around to get a clear signal, I had mine almost horizontal. You can also buy or build a small Yagi. An online search will find several designs.


Frequency list for AO-91

Memory Your Transmit (Sat Uplink) Frequency

(With 67 Hz Tone)

Your Receive (Sat Downlink) Frequency
Acquisition of Signal (AOS) 435.240 MHz 145.960 MHz
Approaching 435.245 MHz 145.960 MHz
Time of Closest Approach (TCA) 435.250 MHz 145.960 MHz
Departing 435.255 MHz 145.960 MHz
Loss of Signal (LOS) 435.260 MHz 145.960 MHz

Good luck!

Larry VE7VJ

Some useful links:

YouTube – just type “AO-91” in the search. There are lots of videos.

FM Satellites: Good Operating Practices for Beginning and Experienced Operators

Online satellite tracking

 Online Maidenhead grid locator map



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