Sub-9kHz amateur radio

Some years ago I experimented on amateur radio below 9kHz. To receive amateur radiated signals at range needs very stable TX signals, very narrow filters and integration periods measured in hours or days. Just listening will not work! Luckily the software needed is freely available on the Internet. 

The photo shows G3XIZ. The frequency is Hertz!! My antenna was the earth-electrode "antenna" in the ground. 

It is some years since I last experimented on real VLF. As I recall, I copied amateur sub-9kHz signals from several European stations including 2 in Germany and 1 in Austria I think.

In the past I have successfully experimented at the far ends of the spectrum from visible light to far ELF. There is no doubt that we still have a lot to learn. At both these ends of the spectrum the equipment and test gear can easily be home-brewed. In many ways this is one of the attractions. My own VLF earth-mode gear was fabricated in the back of the garage as was my light beam gear: low cost and great fun. The second link includes a link to the files on my earth-mode article in RSGB RadCom in 2011.

See https://sites.google.com/site/sub9khz/

See https://sites.google.com/site/g3xbmqrp3/mflf

Some very old blog pages (which are not maintained so do not follow the links on the left) are at https://sites.google.com/site/g3xbmqrp/Home/earthmode. This is a blog about my own experiments with VLF earth-mode.

Narrowboat - NOT amateur radio

This morning we did a walk along Burwell Lode. The photo shows a narrowboat on the Lode. The people on the boat were enjoying the birds including several marsh harriers.

 It feels much colder. 

Sunspots - Friday April 2nd 2021

 Solar flux is 78 and the SSN 0. A=8 and K=1. 

IC-705 antenna tuner

The ICOM AH-705 auto ATU sells for about £300. It is not small and not low cost. They do not even guarantee it is water and dust proof and they do not even quote the worst-case VSWR it can match. 

In my view this is not a great auto ATU. I have no plans to buy one.

See https://www.icomjapan.com/support/manual/3231/

Tea in the garden - NOT amateur radio

A few days ago we had tea in the garden in the sunshine as the photo shows. Today is much cooler and over the Easter weekend it is expected to be even colder. 

This is our older son on the right. He lives in the same village. Until recently he has only been to the door with his mask on.

5.5G and 6G

We are just rolling out 5G. Already there is talk of 5.5G and 6G!  I cannot imagine what this would be.

Southgate News has a piece about an upcoming talk.

See http://www.southgatearc.org/news/2021/march/5-5g-and-6g-for-2030.htm#.YGXV12jYrrc

IC-705 on the air

IC-705

Last night, I tried my IC-705 on the air for the first time.  I accessed the GB3PI repeater and went on the FM CDARC net on 2m. At first I did not know how to set up the CTCSS tone for the repeater. I have lots to learn. 

In the coming days I want to try FT8 and D-star. 

The RX seems to work well even on LF with good reception of DCF77 on 77.5kHz with the earth-electrode "antenna" in the ground.  It, so far, fits my operating well. I was surprised to get so many GPS satellites with the rig indoors in the usual operating position.

ICOM has done a great job.   

I have ordered the Radio Today guide to the IC-705 from the RSGB.

Solar data

My favourite site for solar data is usually updated very early in the month. This usually happens on the first or second day of the month.

See http://www.solen.info/solar/ .

UPDATE 1011z:   I see the page has just been updated.

UPDATE 1910z:  See http://www.solen.info/solar/images/comparison_recent_cycles.png . At the moment we do not look on track for a great cycle 25. It looks very similar to the last cycle.

Outside King's - NOT amateur radio

Usually Cambridge is a "must see" for foreign visitors. This year things are very different without visitors from overseas.  It is good to see people social distancing.

Sunspots - Thursday April 1st 2021

Solar flux is 74 and the SSN 0. A=10 and K=3.