Solar flux is 154 and the SSN 127. A=4 and K=2.
13 Apr 2023
Repeater closing
This morning I heard that the GB3YT ATV repeater is to permanently close this summer as the owners are getting older and can't climb ladders. How many will follow? I can imagine quite a few repeaters going with a combination of high site costs, old age and low usage. Many repeaters are totally quiet for hours on end.
12 Apr 2023
70cm FT8 activity contest
This contest starts at 1900z tonight. I usually go on with my 2.5W to my 2m big-wheel omni antenna for about 30 minutes. I may well stay on RX until much later in the evening to see which stations come through.
UPDATE 2115z: After 2.25 hours, 24 stations spotted (see map). What a difference from the UKAC last night! It would seem many now prefer FT8 to SSB.
Threatening sky - NOT amateur radio
We have seen the extremes in our weather today. We have had rain, strong winds, sunshine, but no snow!
Our changing hobby
In some way or other, I have been involved in amateur radio since 1961. Many changes have occurred since then.
When I started, the only real way to talk across the world was if you were a radio amateur. This was the case until the internet came along and anybody could talk across the world with video for free. Since then, amateur radio has evolved. Yes, some still come on the air just to chat, but this number is getting smaller each year as those that remember amateur radio long ago, get older and frailer. Instead, many come on to work new DX, often with modes like FT8. Others come on to experiment or try new things like satellites, ATV or moonbounce.
In my (heretical) view this is how the future looks. It may very well be wrong!
- In 20 years, the Amateur Radio Service will cease.
- Amateur radio will merge with licence free services like CB and ISM.
- Callsigns will be optional and handled by national radio societies for those that want them.
- The Chinese will dominate amateur radio manufacture.
- Everyone will be able to operate licence free as long as interference is not caused and they operate in bands allocated only.
- There will be far fewer magazines.
- There will be far fewer dedicated amateur transceivers.
Puzzled - NOT amateur radio
In centuries past, there have been some amazing places made in the name of Christianity and Islam. There is little doubt that these we made by very devout believers. What puzzles me is that these amazing places got built at all!
All the religions of the world have incredible places and statues. Probably most people on planet Earth have some sort of religious faith. I cannot believe any one of these is "right" and the rest "wrong".
So, as I have said many times before, I prefer to think that all faiths are hints at the truth, not the complete picture.
At the time many sacred texts were written, people believed in witches and things which today we would find bizarre.
Maybe there is a better explanation of events so long ago that was interpreted differently back then?
The Backs yesterday - NOT amateur radio
The Backs are what the backs of the Cambridge colleges are known as. They back onto the R.Cam, famous for punting! The photo shows the approach to King's College yesterday. I don't think I have posted it before. The photo has appeared in many places already, so if this is twice, please accept my apologies.
10m QRP FT8 (Wednesday) with the QDX
At the moment I am on 10m FT8 with the QRP QDX rig. So far today (after about 15 minutes) 11 stations have spotted me. The QDX is tiny!!
UPDATE 1143z: 13 stations spotting me today (see map).
Other sites
This is just a reminder of the other sites I maintain. Hopefully, you will find some inspiration on these. Overall, I hope you have fun.
http://www.g3xbm.co.uk
https://www.youtube.com/@G3XBM
http://g3xbm-qrp.blogspot.com/
CDARC Wednesday Net
At 1900z on Wednesday evenings, the Cambridge and district amateur radio club (CDARC) holds a very informal net on 145.55 MHz FM. Anyone in range is welcome whether a club member or not. Usually there are between 3 and 7 members on. Polarisation is vertical and there is a web SDR if you are having difficulties receiving. I thought the link for this SDR was on the CDARC website, but cannot find it.
Most people on the net are in the greater Cambridge area (surrounding villages). The net usually lasts for 20-60 minutes, but people come and go as they want. It is rarely technical!
See cdarcvhfrx.hopto.org:8073 for the webSDR.
Matching the earth-electrode antenna in the ground
To allow the auto ATU in the FT-710 to match the earth-electrode antenna on 80m (see the excellent results yesterday) I had to use this transformer. As you can see, it is not pretty!! With it, the load presented to the FT-710 was obviously less than 3:1 as it matched well.
12 years ago
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| Earth-mode experiments in 2011 |
This was my earth-mode signal 4.5km away from home in 2011 at 1.095 kHz using Spectran software on the PC. Strictly speaking, I suppose this is ULF!
11 Apr 2023
70cm activity contest
After copying no stations at all (!) I gave up. I expect the next 70cm FT8 activity contest will be much better!
80m FT8 (Tuesday)
As 6m was so poor, I QSYed to 80m FT8 using the earth-electrode "antenna" in the ground. Although I am receiving spots of my signal from right across Europe, it says I am receiving none. This is rubbish as I can see loads of stations locally. Either there is a delay with uploads from me or, more probably, my spots are not getting to PSKreporter. Shortly I shall do reset to see if this cures it.
UPDATE 1922z: The reset did the trick with lots of spots on RX. On TX 36 unique station spots of me so far.
UPDATE 2119z: 112 stations have spotted my 10W 80m FT8 TX this evening. Now QRT on all bands.
6m FT8 (Tuesday)
E-field probes (EFPs)
These are tiny receive only antennas that can work extremely effectively at VLF, LF and MF where external noise is usually the dominant factor. I guess as local external noise is increasingly the dominating factor, these will be as effective as a "big" antenna at even higher frequencies. At LF they can be only a few centimetres long, but be as effective as antennas hundreds of metre long.
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| EFP on a mag mount for 2200m RX |
As the signal decreases, so does the external noise! Overall, nothing is lost. There is no advantage by using a large antenna at low frequencies for receive only. For TX efficiency, a large antenna and good earth help! A popular EFP design is that PA0RDT (Google it). I have made versions for LF and VLF with a tuned peak as shown in the circuit.
See https://sites.google.com/view/g3xbm4/home/antennas/137khz-efp-rx-antenna .
Double rainbow - NOT amateur radio
April in the UK is a strange month. Some days can be warm and sunny, whereas others can be cold. Yesterday was a mix of sunshine and showers. The photo of the double rainbow was taken in haste from the lounge window. A few minutes later it had gone.
10 Apr 2023
630m WSPR RX
At about 1940z, I switched to 630m WSPR RX with the earth-electrode "antenna" in the ground. So far, no spots.
UPDATE 2126z: Several WSPR spots of DC0DX (467km) at up to -9dB S/N.
Earth-mode paper
Someone asked for access to this file. It is now open so if you have this link you should be able to read it. It was sent to me some years ago.
See https://drive.google.com/file/d/16vtYNznORclXJTfpaT-RC7Z3IV8RKqyi/view?usp=sharing .
6m FT8 (Monday)
For about an hour, I have been on 6m FT8. So far, 13 stations have spotted me and 1 have had 1 QSO. I noticed the BNC plug was intermittent. Mending it took about an hour. In years gone by this would have taken me 5 minutes.
80m FT8 (Monday)
At 1255z, I moved from 160m FT8 (no spots) to 80m FT8 using the earth-electrode "antenna" in the ground. The FT8 frequency on 80m seems to be 3.573 MHz.
160m FT8 (Monday)
As my earth-electrode "antenna" is now matched, I am currently using it on 160m FT8 with 10W from the FT-710. No spots, although I am not surprised in daylight. I must double check on the 160m FT8 frequency in Europe. I have never tried FT8 on topband. I have used WSPR in the past. Currently I am on 1840 kHz FT8, which seems right.
UPDATE 1120z: This looks a useful resource for digital modes in Europe. See https://www.pa8s.nl/knowledge-base/frequencies-for-digital-modes/
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| Spots of me at 1814z |
Museum open again - NOT amateur radio
Yesterday, after what has seemed a long winter, our local museum and windmill next door reopened. The weather was sunny and pleasant. Parking near our house is not usually an issue. It was yesterday!!
Monday plans
My main aim today is to match my earth-electrode "antenna" on MF. I I can do this, I can try it on FT8 or WSPR TX on 160m or 80m.
Later, I may try 10m QRP FT8 again with the QDX, although it does not teach me much - I know less than 5W of FT8 can get spotted across the planet. All these stations could be worked, but I do not have the energy to chase these!
UPDATE 1021z: After adding more turns to the primary of my 3C90 transformer I can get a perfect match on 160m and 80m with my earth electrode "antenna" with the auto-ATU in the FT-710. I shall try 160m WSPR or FT8 tonight!
2m activty contest (UKAC) last week
Last Tuesday was the activity contest organised by the RSGB. My incredible score (I am joking!!) has just been submitted as I almost forgot. Tomorrow evening is the 70cm activity contest.
The impression I am getting is interest in this contest is waning with the FT8 contest on the following evening doing better. This is pity as it is a very "un"contest contest with people happy to see the activity levels up. I have been taking part for several years.
The stations contacted are shown on the map.Earth-electrode "antenna"
My earth-electrode "antenna" has been reinstalled.
Much to my surprise I am unable to tune it using the internal auto-ATU suggesting the impedance is greater than 150 ohms.
I shall have to try a new matching transformer to bring it in range of my auto-ATU. This make take a few goes. I want a good match at MF.
9 Apr 2023
Rain Gauge - NOT amateur radio
One of my wife's Christmas presents was a rain gauge. We record the rain that has fallen each day and total up the month. February was very dry and, so far, in March, we have already had more than the whole of February!
2m Fredbox QSO
This was in 2011 and shows me in QSO with the 10mW 2m AM Fredbox. Many years ago I had a cross channel QSO with it handheld. These days it is hard enough having an FM QSO on 2m!
See https://sites.google.com/view/g3xbm4/home/vhfuhfmicrowaves/homebrew/fredbox.
Grand master? - NOT amateur radio
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| Playing chess with one of my grandsons |
8m band
This is midway between 10m and 6m. It is only allocated to the Amateur Radio Service and in a few countries it has been allocated for experiments only to a handful of stations. In some cases this is very reluctantly.
It is my view that others could gain access without a licence in the ISM band from 40.66-40.70 MHz as long as local conditions are fully met. You need to convince yourself of the legality. In the UK this means 10mW ERP. On WSPR, this can go a very long way. In Australia 5mW of 8m WSPR has spanned 5000km!
In the next few months in the Es season 10mW ERP will definitely allow UK stations to be copied across Europe on 8m WSPR.
With sunspot numbers high at the moment, the F2 MUF exceeds 42MHz on occasions so very long distances are possible at times with FT8 or WSPR even with QRP.
See https://sites.google.com/view/g3xbm4/home/vhfuhfmicrowaves/8m-band .
8 Apr 2023
Soon to be obscured - NOT amateur radio
Yesterday, some of the hedge on the south side of our garden was cut back. The view of the village church about 300m away is now very good. In a few weeks' time this will be obscured by leaves on the trees.
Now this foliage is cut back I want to replace my earth-electrode "antenna". In a few weeks this will be much harder.
10m QRP FT8 (Saturday)
My 10m FT8 with the tiny QDX transceiver was turned on at 0835z.
UPDATE 1140z: 149 stations spotted and 42 stations have spotted my 10m FT8 QRP today with the QDX.
Plans for today
One of my aims for today is to reinstall my earth-electrode antenna in the ground and try it out on MF with the FT-710. I shall probably go on 12m or 10m FT8 with the tiny QDX.



















