2-way QSO on the 8.97kHz "Dreamers Band"

DJ2LF and DF6NM held what was probably the first two-way contact on 8.97 kHz. The distance between them was 20.2 km, well outside the reactive near field zone (λ/2π = 5.3 km). In each case the radiated power was about 5uW. They used a special QSO procedure using dual frequencies. Congratulations to both stations.

Noctilucent Clouds and microwave DX?

Noctilucent, very high altitude, night time visible, clouds are becoming more common and at lower latitudes. This may be a result of climate change. One phenomenon associated with these is strong microwave radar echoes, raising the possibilty of very long distance DX by reflection from these on bands like 10GHz. This is an area ripe for experimentation but I am unaware of ANY groups anywhere investigating this exciting new propagation mode.

There is a  link between noctilucent clouds and the solar cycle with NLC activity peaking just after solar minimum, possibly because low solar activity allows the upper atmosphere to cool, promoting the growth of ice crystals that make up the clouds.  See http://spaceweather.com/

SWLing in the 1960s

Back in 1961/62, when I first got interested in shortwave listening, a friend of mine and I had an intercom across our back gardens with a long piece of twin flex and a couple of DLR5 headsets. Now my friend's dad was a bank manager and he was "rich". Paul's dad bought him a Perdio 102 multiband receiver which made me green with envy! So, late at night, under the bedclothes, we'd both share listening on the Perdio102: Paul would put it to listen on 2.182MHz (the trawler band calling frequency) and we'd often hear an emergency and the local lifeboat being called out. We'd listen for hours. On this same receiver I recall being amazed at hearing South America hams on AM. We both became hooked and not many years later got our licences. See also the radio museum pages at http://www.radiomuseum.org/r/perdio_multiband_102.html

HF transceiver ideas site

Vanyi Istvan Vanyi YO5OFJ has an excellent website with links to a whole list of HF transceiver designs from around the world. Most are QRP designs with links to the originating sites.

Amateur Radio Wiki

Not sure how I'd managed to miss this amateur radio wiki site before, but it looks worthwhile bookmarking.  Being a wiki, it allows users to add or modify content in a similar way to Wikipedia. It has some useful links and data.

Elecraft K1 stand idea

Someone was asking about a stand to angle the Elecraft K1 transceiver at a suitable angle on the operating desk. A commercial version is available, but I found a simpler solution: two large rubber feet at the front and two small ones at the back. This angles the rig up about 10-20 degrees and is perfect for operating on a desk.

6m WSPR

Just decided to do a little 6m WSPR beaconing this afternoon and evening. So far no reports of my signal, but I'm copying EA4BMG quite well. There are many more signals weakly visible on the WSPR screen but these have Doppler shift which must confuse the software decoder as only EA4BMG has been repeatedly decoded.

Concorde to fly again?

There are moves afoot to get Concorde, the supersonic jet, flying again on memorial flights and it is possible it may yet fly over London at the 2012 Olympic Games opening. The only time I've been on Concorde was at Duxford Airport in Cambridgeshire in a static display. My wife's brother used to work for BT and fly to the USA and back in a day using Concorde so he could hold meetings in New York on a day trip - how times change!

See http://news.bbc.co.uk/1/hi/world/europe/8712806.stm

The latest VLF receiver

Here is a picture of the latest version of my VLF 1-2kHz receiver for use with my 80cm loop. The version before this (Wednesday) had one less Sallen-Key active high pass filter and was able to copy my 4W grounded electrode transmissions "by ear" at 0.5kms. This latest version now has 2 sections of 50Hz active high pass filtering so should offer better S/N at the limit of range. The audio above 2kHz is attenuated by the passive LPF.

RockMite 20 QRP build video (N2JMB)

Just came across this video showing the build of a Small Wonder Labs Rock Mite 20 QRP transceiver.