Showing posts with label 6m dx. Show all posts
Showing posts with label 6m dx. Show all posts

25 Oct 2009

CQWW contest summary - 10m was great

With darkness falling now 10m is going quiet after an exciting 2 days. In the end, my 5W SSB and halo antenna worked 35 stations in 20 countries. DX from outside Europe was not workable this time but I was hearing CX, PY, ZS, 6W, etc so conditions were definitely not bad. Although there were a couple of stateside stations worked from Europe, I did not manage to hear them. The slight upturn in sunspot activity came just at the right time.

16 Jul 2009

6m Super DX

For the last few days I have been in South Devon on holiday. Some evenings I have been out looking for skeds with the SixBox 6m QRP AM transceiver but two tests failed even with 2W AM from the FT817 and the 1/4wave magmount, so no QSOs with the baby rig yet. However, I managed several European DX QSOs with 6m QRP SSB, all with good reports.

Last night was exceptional on 6m: YV4DDK, FM5AA and 9Y4D all coming through at good strength (at times) on 6m SSB with just a 1/4wave magmount antenna! Although I tried calling the YV4 at one point I knew it was pointless with all the super-QRO stations with big beams calling them. Still, it was good to HEAR such super-DX on 6m (8000kms) with such a simple portable station.

19 Jun 2009

Noctilucent cloud DX - microwave mega DX mode?

There was a MOST interesting note on the ARRL propagation report tonight:

"Noctilucent Clouds Return - As reported at spaceweather.com on June 1, the first noctilucent clouds (NLC) of the 2009 season were sighted over Russia on May 27. NLCs typically appear about 20 days prior to the summer solstice, increase quickly to a high summer level, and then disappear about 50 days after the summer solstice. These clouds are mostly a high latitude phenomenon, and are believed to be composed of ice crystals. VHF radars see very strong echoes from these clouds, and since they are at mesospheric heights (80 to 90 km), they are also known as polar mesosphere summer echoes (PMSE). These clouds are hypothesized by JE1BMJ and others to be responsible for 6m propagation across high latitudes (for example,
from the East Coast of North America to Japan) during the northern hemisphere summer. This mode of propagation has been dubbed Summer Solstice Short-path Propagation (SSSP). Check out page 34 of the February 2009 issue of WorldRadio Online (available free at
www.cq-amateur-radio.com/wr_back_issues.html) for a general discussion of PMSE and SSSP and for references in the technical literature. To reiterate, SSSP is still just a theory,
but the occurrences of QSOs appear to match the occurrence pattern of PMSE."

Now, there is also evidence (from radar returns) that microwave DX might be possible using the same noctilucent clouds, possibly allowing superb DX possibilities on 10GHz possibly even with low power.

This is a whole area of future ham research just waiting to be exploited. It may be one upside of global warming as these high altitude clouds are now more common than hitherto.

For more on these mesospheric clouds see http://www.chiandh.me.uk/p/Noctilucent_cloud#Results