Working F0-29

Now that I have worked an FM satellite (in my case SO-50) the next challenge was to try a SSB satellite.

The basics would be the same I figured, except I would need to use my Yaesu FT-817. In fact, all I needed to do was to switch rigs and take into account that I would be needing to run to 817 off my 7 a/h SLAB, which I would need to slip into a spare camera bag so I could carry it over one shoulder.

The battery is in a camera bag hanging on my left side, and the FT-817 is slung around my neck (I knew the strap would come in handy some day).

So that I could work the satellite single handed out in the field without the aid of computer software, this is what I did:

  1. Set the rig into split mode
  2. Set VFO A to 145.960. This is the uplink.
  3. Set VFO B to 435.840. This is the down link
  4. Make sure the antenna connection is set to the front connector on the radio
  5. Keep the radio set to VFO B

When I saw the satellite is within range (using Satellite Explorer on my PC), I went outside and pointed the antenna into the rough direction of the satellite’s approach. This was roughly north. Then I put out a call (the radio switches to VFO A automatically when the PTT is activated but returns to VFO B when it is released. Then I immediately began tuning down the band to listen for replies.

Sure enough, I heard Wal VK4CBW, George VK2WEL and Geoff VK2ZAZ. I had a very satisfying QSO with them, but it was challenging having to continually alter the receive frequency by hand during the receive cycle while altering the direction of the antenna to take into account changes to direction as well as height, all at the same time.

Next is to think about improving my operating setup, perhaps with some form of automatic tracking capability.



Working Satellite SO-50

One aspect of amateur radio that I am enjoying lately is working the FM satellite SO-50. To do so I use my Boafeng GT-3TP dual band hand held and an Elk log periodic antenna that I have mounted on a camera tripod.

My basic satellite communications setup.

SO-50 carries several experiments, including a mode J FM amateur repeater experiment operating on 145.850 MHz uplink and 436.795 MHz downlink. The repeater is available to amateurs worldwide as power permits, using a 67.0 Hertz PL tone on the uplink, for on-demand activation. The repeater consists of a miniature VHF receiver with sensitivity of -124dBm, having an IF bandwidth of 15 KHz. The receive antenna is a 1/4 wave vertical mounted in the top corner of the spacecraft. The receive audio is filtered and conditioned then gated in the control electronics prior to feeding it to the 250mW UHF transmitter. The downlink antenna is a 1/4 wave mounted in the bottom corner of the spacecraft and canted at 45 degrees inward.

The Elk was loaned to me by Wal, VK4CBW, an avid satellite fan who lives down the road from me. The antenna is basically a held-held job but I do find it gets a bit heavy after a while, hence the tripod.

Today SO-50 was within range at 4.56pm, so I put out a call and was answered by Roy, VK4ZQ, from Nundah in Queensland. And although Roy isn’t that far from me, the satellite is. The apogee height is 665km, which means at its furthermost distance from the earth, it is 665km away. Not bad for a two-way FM contact.