VLF tests last weekend

Last weekend saw both DK7FC and DF6NM transmitting with <100mW ERP on VLF. Their signals were successfully received by many stations across Europe with best DX for DK7FC/P being 2404km to Iceland. G3ZJO successfully received a DFCW60 message from DK7FC/P.

Both stations described their activity and results in brief reports which you can find via links at https://sites.google.com/site/sub9khz/news .

VLF test Saturday June 18th (DK7FC/P)

Tomorrow morning Stefan DK7FC/P will be testing for the first time in many months using his kite supported VLF antenna. He will be transmitting from mid Germany on 8.9700000kHz (precisely GPS locked) from around 0600z Saturday. His ERP will be in the 50-250mW region.

If you have Spectrum Laboratory (free software) and a suitable E-field probe or loop antenna then this is a great chance to see if you can detect his signals. The last time he tested he was quite a good signal in the UK and was received by several suitably equipped stations.

It is unlikely his signal will be audible, but he should be a clear trace on the SL screen with a suitably narrow bandwidth setting (4.52mHz or less). Frequency accuracy is paramount and you will need a Spectum Lab config file that "locks" onto GBZ or similar to ensure you know precisely where to look. Initial tests will be with a long carrier followed by characters in very slow DFCW or QRSS.

You do NOT need a VLF communications receiver: just a loop or E-field probe and a small audio preamp feeding the sound card of a PC. This is amateur radio "at the edge" in the same way that optical comms is .....but at the other end of the spectrum. Great fun and a nice challenge.

I shall be looking and streaming the received signals to my VLF grabber visible at https://sites.google.com/site/sub9khz/vlf-grabbers/xbm-grabber . It is also possible that G3ZJO will have his (better) VLF grabber on too at http://g3zjo.bplaced.net/ . The RSGB LF-reflector will carry updates in the event of the kite blowing away, going QRT for storms etc..

Scientists predict rare 'hibernation' of sunspots

For years, scientists have been predicting the Sun would by around 2012 move into solar maximum, a period of intense flares and sunspot activity, but lately a curious calm has suggested quite the opposite.

See http://news.yahoo.com/s/afp/20110614/ts_afp/usspacesun

23cm activity contest next Tuesday

Having had some fun in both the 2m and 70cm cumulative contests today and last Tuesday my thoughts are now turning to the next contest which is on 23cm next Tuesday evening. As I don't have any transmit or antennas on that band I shall just listen. Once again I shall have to make a suitable antenna and the most likely will be either a small 4 el beam made from thick wire or a 23cm Moxon 2 element beam which would be about the size of my hand. My 23cm converter has not been used for well over 15 years so that will need to be checked carefully and the LO crystal re-netted.

70cm activity contest - a brilliant /P evening

Stations worked 70cms UKAC 14/6/11

My tiny 4el 70cm yagi made from wood and a couple of coat hangers worked very well this evening netting me 17 QSOs in just over 1 hour of operating with 5W RF from the FT817. Best DX worked was 191km although I heard both GD8EXI and GI6ATZ at much greater distances.

432MHz Contest - June 14th

Tuesday June 14th is the 70cms activity contest from 1900-2100z. I've made a small 4 element yagi for portable use and this mounts on a small 20mm diameter pvc conduit pipe fixed in the window of my car (see image). It is all very lightweight. At the intended portable site I was able to copy the GB3BSC beacon some 200km away today in a trial run. All being well I should be able to work a few stations around the country.

Solar peak THIS year?

The more I look at the data the more convinced I am that we are now reaching (or may have already passed?) the peak of solar cycle 24 much earlier than expected and at a very low peak level. See some interesting data at http://www.solen.info/solar/polarfields/polar.html about solar magnetic field reversals and the latest plot of solar flux and sunspots at http://www.solen.info .  For several months now the general smoothed trend, ignoring blips, is downwards.  We may never again experience the exceptional HF conditions seen at the peak of some sunspot cycles in the last 50 years, at least not in my lifetime.

6m Super DX - use WSPR!

We are now in the season of super-DX Es openings on 6m when the band opens spectacularly across the Atlantic to the USA and the Caribbean as well as northern South America and Africa. WSPR could be a superb tool to help track fleeting openings over these very long paths, but we need more stations on 6m WSPR for this to be possible. Ideally stations need to be operational 24/7 on 6m but as a minimum from around 1100-2400z and located in Europe, the eastern USA, Canada, the Caribbean and northern South America. When not busy on 137kHz I propose to make 6m my WSPR home this summer. If the band opens across the Atlantic then 5W to a small vertical or dipole should be enough to get transatlantic spots. Let's fill the 6m WSPR slot with activity.

6m WSPR today

Good conditions on 50MHz today with WSPR spots from GM4SLV, PA0O and CN8LI when using 5W to the V2000 vertical antenna. The report from John in the Shetlands was -2dB S/N suggesting just a few milliwatts would have been enough. PA0O is interesting as it may not be Es but tropo propagation as the distance is pretty short for Es skip.

137.5kHz WSPR

This evening F8BOJ was testing on 137.5kHz WSPR so I had a go at copying him, although he is around 700km south of me in the null of my fixed loop. G4WGT was copied but so far no sign of F8BOJ. I've also been TXing with 100uW ERP but no reports this evening although GW3UCJ thinks he may be seeing signs of my bursts but too weak to decode.