Posts Tagged ‘radio propagation’
Trans-Tasman on VHF/UHF
Quite a few 2m and 70cm contacts have been made between VK and ZL over the past few weeks. The distance, depending on QTHs in question, are around the 2200 km mark.
Contacts made this way are mainly due to tropospheric propagation. High pressure zones, and high temperatures forming ducts aid and abet those seeking contacts.
It’s harder for me to work into ZL because I’m about 120 km inland – and 1 km high. It’s harder for my signals to enter a duct, or otherwise made it across the water.
Low activity levels / meteor scatter
I’ve not a heard a chirp on the 2m, 6m or 10m bands for weeks. I monitor beacons on a regular basis, and leave the receivers running on the 2m and 6m SSB calling frequencies.
The merging of the low winter and low solar cycle periods leave little activity.
I have to qualify the above statements by adding that I don’t live in front the receivers so I will miss things now and again
but in general there’s not a lot happening.
I need to get my 2m meteor scatter setup up and running again. There’s usually always some level of activity in the mornings. I can’t work further south than Rex, VK7MO, in Tasmania. After that there’s nothing but ocean before hitting Antartica. Working into New Zealand would be a challenge – from this QTH it’s right on the accepted range for “normal” MS working at around 2200 km (1400 miles). With a little “assist” from a duct, though, it could be possible.
10m / 6m /2m
I listened, off and on, for beacons on 6m and 10m today. I can categorically state that, with one exception, both bands were pretty dead! The exception was that I could hear the familiar old chirpy beacon from Adelaide, VK5WI, for several hours on 10m (28.260 Mhz).
I also left the receiver running on the 6m and 2m SSB calling channels whilstever I was in the shack today. Nothing heard. Not even a meteor ping.
E’s on 6m
I hadn’t listened on 6m for some months. I don’t have any antenna other than my HF vertical which tunes on 6m quite reasonably. I was a little surprised to find some beacons:
FK8SIX on New Caledonia at 0254z VK4ABP at Longreach at 0510z VK4RTL at Townsville at 0516z
On SSB I heard John, VK4FNQ, in QSO with VK1VP in Canberra (I couldn’t hear the latter).
Aurora from the old log book
Another golden oldie. While reminiscing through my old logs, I note that the first contact I had on 2m via an aurora was on September 15, 1974. I made 47 QSO’s across 6 countries in the 12 hours between 3pm and 3am local time. All on SSB, all using 10 watts!
At that time I was living in Aberdeen, Scotland, and using the callsign GM8IKT. Aberdeen being over 57 degrees north of the equator was a great site for aurora – unlike my present QTH which is 30 degrees south of the equator. I’ve never heard anything auroral from here.
Space Weather dot Com
The sun plays an important part in assisting, of defeating, our attempts to communicate over long distances, on different frequencies. The 11-year solar cycle (or is it really a 22 year cycle?) dictates whether the 50 Mhz band, for example, will provide global DX, or just white noise coming from our receivers.
A website that provides useful information about the state of the sun, sunspots and flares, and other space phenomena is spaceweather.com. There are usually some spectacular photographs in there too.
Indicator for enhanced VHF/UHF conditions
After all these years (over 30) of operating on VHF, I still enjoy those too few days when VHF signals are enhanced for one reason or another. At the moment, being mid-winter, things are pretty quiet. I keep an eye on William Hepburn’s Tropospheric Ducting Forecast web pages at http://home.cogeco.ca/~dxinfo/tropo_oce.html just to see what might be coming up. It can be an extremely good indicator of promising conditions.
I look forward to operating on UHF too once I get some antennas operational on the new tower!
