DK7FC's VLF tests a great success

Stefan's latest VLF kite antenna transmissions at 8.97kHz and even lower frequencies were a great success yesterday with reception as far as Eire, Italy, Poland and the UK. The attached shot shows the signal on 2 frequencies as received by Renato IK1QFK in Italy.

M0BMU receiving DK7FC's 8.97kHz signal 10dB S/N

Jim reports that Stefan's DK7FC's 8.97kHz test signal is visible at 10dB S/N in Tring UK this morning. He is also visible on other grabbers in Europe. This is an excellent report and further encouragement for those of us taking our first (QRP) steps on the 33km band.

More 500kHz 2mW ERP DX reports this evening

This evening I switched back to 500kHz from 137kHz WSPR earlier in the day. Yet again good WSPR reports from GM4SLV and OH1LSQ (1733km) who received me as early as 1716z.

8.7 to 9.1kHz NoV received

This morning I received my NoV from OFCOM to operate legally around 9kHz (see copy on RHS - click to enlarge).

Details are:

• 1yr duration
  
• 8.7kHz - 9.1kHz 
• 100mW EIRP
• Modes not specified (long periodic modes preferred by Met Office)
• Met Office have to be informed of, and approve, operating periods and be sent logs
• Home QTH or /P locations only with prior Met Office approval

No firm plans yet when I'll start local tests on this band, but within couple of weeks with QRP WSPR and QRSS. I'll put a copy of the NoV on my website in the next few hours.

Struggling on 137.5kHz

Using the same TX output power (5W) and the same loop antenna I'm finding life is VERY much harder on 137.5kHz compared with 500kHz. Last night I was being copied right across Europe on 500kHz but tonight only 2 stations (best DX 69km) are able to copy me on 137.5kHz WSPR. The reason is simple: the radiation resistance is so much lower, so losses become more significant, and the ERP is very considerably lower. There is no doubt that to increase my "sphere of influence" on 137.5kHz I'll have to make some big improvements.

New DX record on 500kHz WSPR

This evening, quite unexpectedly, I got a string of reports on 500kHz from OH1LSQ in KP03sd at an astounding distance of 1733km. To me these are amazing reports pushing my best DX on the band with just a few milliwatts ERP to new levels.  What surprises me is how well a very simple wire loop works as a TX antenna: the wire is just 1mm diameter, with a loop area of around 70m square with part of the loop on the ground buried in wet grass. I now believe almost anything is possible!

Vertical loop success on 500kHz QRP

This evening I've been WSPRing on 500kHz running about 2mW ERP from my thin vertical wire loop with an area of around 70 sq metres. The bottom of the loop just runs along the ground and at the moment is buried in the long wet grass! Despite this, my signal is being decoded in G, ON, PA and GM with best DX tonight 896km to GM4SLV up in the Shetland Is.

Further 8.97kHz test this Saturday

DL7FC, Stefan, is planning another VLF kite antenna test this weekend Oct 23rd. I am assuming he will be on 8.97kHz again.

Additional SAQ VLF transmission

From SM6NM/Lars

There will be a transmission with the Alexanderson alternator on 17,2 kHz on United Nations Day Oct 24 2010 at 11:00 UTC. Start up and tuning from about 10:30 UTC. This time we do not require any QSL-reports and will not verify. We intend to continue with our annual transmission on Christmas Eve (morning), Dec 24, at 08:00 UTC with tuning up from 07:30 UTC. D.S.

 

Holiday in South Africa - just back

No posts here for the last few weeks as my wife and I had been on holiday in South Africa. It was an amazing holiday organised by Saga and we saw some fantastic places, people and animals. Saga organise holidays for the over-50s and we were not sure what to expect, but the hotels, food, transport, and everything well exceeded expectations and the group we were with was a real mix of interesting people. The whole experience was something to feed on for years to come. For example, seeing the "Big 5" wild animals (and many more) in the Kruger National Park, seeing no less than 6 southern right whales at one spot from the shore near Cape Town and getting to within a couple of metres of wild penguins on a beach near Simonstown. Also, seeing the highlands of Lesotho where people still live a subsistence existence in huts made of dung, straw and sand without electricity and the basics we take for granted.