LF and VLF ideas

In recent years there has been an increasing interest in amateur VLF work. You may find some ideas on my webpage.

Although big antennas and high power help on TX, this is not so on RX where some very compact antennas can be really effective. E-field probes are very small yet are very effective VLF RX antennas. They are every bit as effective as much larger antennas.

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

Sunspots - Thursday August 22nd 2019

Solar flux is 66 today and the SSN 0. A=5 and K=1.

2m FT8

Well, I thought something was wrong! Then I found that my UHF adaptor was not in properly. My recent 2m FT8 CQ was widely spotted, but no QSOs resulted. Best TX (10W to the big-wheel) DX was EI2FG (565km) in southern Eire. Also spotting me were 3 Cornish stations as well as a French station and a Belgian station.

On 2m FT8 RX DF6PW (562km) is the best DX.

2m FT8 certainly works!

UPDATE 1930z:  My last 2m FT8 CQ was copied by 6 stations, although no QSOs resulted.

UPDATE 2025z: 5 stations spotted my 10W FT8 2m CQ just now, including one station in Cornwall. No QSOs resulted.

UPDATE 2054z: 26 stations spotted this evening on 2m FT8 RX with the best DX being DJ6AG (689km) deep into Germany. All this on the big-wheel omni.

Back on 6m FT8

Earlier we went by train to Peterborough, where we went to the Gaia exhibition and had lunch.

Now we are home again, I am on 6m FT8. After a few CQ calls, I am currently RX only. On 6m FT8 TX I was spotted by LA7DHA (1902km) way up in Norway. I assume this is Es. Other spots were by stations in  England.

So far on 6m FT8 RX just one G spotted.

Every time I go on 6m FT8 TX I seem to be spotted at great range, presumably by Es. I think it is disappointing that people desert the band in August thinking that the Es season is over. Clearly with FT8, we are seeing Es every day so far this month that I have been active.

UPDATE 1540z: Another FT8 CQ (10W) was spotted by 6 stations with (again) LA7DHA (1902km) spotting me. Still just one spot on 6m FT8 RX.

Globe - NOT amateur radio

At the moment there is an exhibition on inside Peterborough Cathedral called "Gaia". The centre piece in the nave is a 7m diameter globe of the Earth (see photo). It is very impressive and free in the daylight hours.  They charge in the evenings when there is music and the globe is illuminated.

End fed half wave antennas

The problem with end fed half waves is they are a high impedance at the ends. This is often outside the range that can be tuned with auto-ATUs in many modern rigs that tune out mismatches to about 3:1 VSWR. The common solution is to add a matching transformer so the auto-ATU can cope. There are several ideas around.

See https://vk3il.net/projects-antenna/efhw-matching-unit/

Sunspots - Wednesday August 21st 2019

Solar flux is 67 and the sunspot number 0. A=4 and K=1. Still no sunspots!

BREXIT deal? - NOT amateur radio

We have a Prime Minister who is on record as saying that we will be leaving the EU at the end of October deal or no deal. He has also said the chances of a no deal are 1 million to 1 against.

At the moment both the UK and EU seem to be playing chicken to see who blinks first. It seems to me that the divisions are only over the border between Eire and Ulster. Surely to goodness a compromise can be found that suits both the EU and UK?

If a compromise is not worked out, both lose. No-one wants that.

2m FT8

A few moments ago I switched to 2m FT8 TX. 4 spots with best being GI6ATZ (479km). Yet again, I am running just over 10W to the big-wheel omni antenna.

Already a couple of Germans are in the RX log. FT8 makes things possible that simply would not be possible on SSB or CW for me.

UPDATE 2048z: Just worked F6BTP (323km) on 2m FT8. I called him in answer to his CQ call. I was also copied in Germany (562km) and Eire (565km). Quite amazing with just over 10W to an omni antenna.

Punts in the rain - NOT amateur radio

This photo was taken earlier this summer.

We had a shower of rain, so all the punt occupants suddenly erected umbrellas! They are on the Cam just outside Kings College.