12 Apr 2022

PI4 versus FT8?

Until today, I did not realise that PSKreporter supported PI4, which is a mode used by some beacons. What I do not know is the sensitivity of PI4 versus FT8. If anyone knows, please tell me.

That projects book

Several people have suggested that I do a book of all my projects. I started it, but have not got too far! It is a lot of hard work, but might be a good idea. What do you think? 

Looking back, I have done several projects and it might be a "good thing" to have them all together. These cover VLF to light (1 kHz to 481 THz) plus some antennas.

Someone in the comments suggested a PDF version, which is not a bad idea. Maybe I should consider this? 

I am not really after money for this, so maybe I should do it and add it as a free download from my website? If anyone wants to give a charity donation, they would be free to do so. If they just want the PDF book, that is their choice.

Hopefully, Practical Wireless, RadCom and QST (maybe others too?) could give the link.

Tenbox

Many years ago, before my stroke, I intended to build a simple 10m phone transceiver aimed at local contacts only. What I had in mind was a 10m version of my 6m Sixbox and 2m Fredbox. 

It used a super-regen RX with isolating pre-amp to avoid radiation, so would not be suitable for DX work. Having said that, it had no problems receiving USA AM stations in the car with just a base loaded whip. 

My idea was to build a rig that could be used when 10m is dead, such as at night or in poor solar years. 10m is a great band and very little used when not "open". 

It is ideal for local contacts as antennas are small especially when compared with 160m. CB antennas work well. 

In my mind was something like the old Heathkit Benton Harbour Lunchboxes (remember those?), but far smaller and on a single simple PCB.

Sadly my stroke got in the way and the project was not completed.  It would be great if someone else completed this project. There may well be better solutions these days.

See https://sites.google.com/view/g3xbm4/home/hf-mf-and-lf/homebrew/10m-am-tenbox .

10m WSPR QRP TX (Tuesday)

At the moment, I am on 10m WSPR TX with 500mW from the W5OLF beacon. So far today, just local spots. 

UPDATE 1052z:  Still just local spots. 

Clunch - NOT amateur radio

This photo shows a house in our village that is having its plaster removed to reveal the clunch beneath. Clunch is a kind of chalk commonly used as a building material locally. 

8m tests (Tuesday)

This morning I am doing MSK144 tests with Paul G9PUV nearby Brighton. I am copying him, but he is not copying me. 

UPDATE 0801z:  Sadly he did not copy me. At times he was very strong, presumably by random MS bursts. I guess with his much higher power they were long enough for me to decode Paul. Being much weaker, it would need a very long burst for me to be decoded at his end. We tried. I am sure with a proper MS shower or Es backscatter, we have a chance. Currently FT8 RX on 8m on 40.680 MHz USB dial.

UPDATE 1314z:  No FT8 spots.  I see both S50B and ZS6WAB are monitoring. I think I have a very modest station, so my "experiment" is really to see how 8m does with a QRP station and small wire antenna.

UPDATE 1345z: Now on 40.680 MHz USB dial FT8 TX again. 2 local spots so far. I have still to have a 2-way exchange of reports on 8m.

UPDATE 1530z:   For about the last hour, I have been on 8m 40.680 MHz FT8 RX. No spots. I must see if I can see the Irish beacon EI1KNH near Dublin on 40.013 MHz sending FT8 for part of its cycle. I may just be possible to copy this beacon by tropo, but I expect it will be strong on MS pings just as the old Rosemarkie beacon GB3RMK was on 6m. Even with my poor 6m antenna it peaked on random MS pings every few minutes.

UPDATE 1652z:  The EI1KNH 8m beacon is not copyable by tropo.

Sunspots - Tuesday April 12th 2022

Solar flux is 99 and the SSN 24.  A=13 and K=1.

11 Apr 2022

10m QRP WSPR TX (Monday)

Once again, I am on 10m WSPR TX with 500mW from my W5OLF beacon. 5 unique stations have spotted me.

UPDATE 1955z:  12 unique stations spotted me today. Quite a good day really.

8m tests (Monday)

 After a brief period on 40.680 MHz USB dial FT8 TX (1 local spot), I am RX only on 8m FT8.  So far, nobody spotted today.

UPDATE 1022z:  Someone has just raised a very interesting question. In the ISM bands 40.66-40.70 MHz his calculations suggest 50uW can legally be used into 50 ohms. I think he calculated that anyone in the UK could legally go on 40 MHz TX without a licence as long as they are in the ISM band. On WSPR, it would not surprise me if 50uW could be detected in central Europe in a decent Es opening. Now, I am no legal expert and have not looked in to this, but if correct it means anyone could legally TX on the ISM band without a licence as long as the ERP was less than 50uW. This is worth checking out. I think you can make up your own callsigns to ID yourself in any reports. As I said, I am not a legal expert and you need to check carefully if this is correct.

This from the OFCOM document about ISM:

“industrial, scientific and medical (ISM) applications (of radio frequency energy): Operation of equipment or appliances designed to generate and use locally radio frequency energy for industrial, scientific, medical, domestic or similar purposes, excluding applications in the field of telecommunications.” 

Maybe the excluding applications in the field of telecommunications is the killer? Mind you, I cannot imagine OFCOM ever policing this!

UPDATE 1341z:  For 8m I just have a low wire dipole which is strung between the support for my 2m big-wheel and the end of my 10m end fed antenna. You may just be able to see it in the photo.


UPDATE 1436z:  About to go on 40.680 MHz USB dial FT8 TX.

UPDATE 2039z:  QRT now. S50B and G9PUV both copied earlier on 8m.  Doing a test on Tuesday from 0600z on 40.680 MHz MSK144 with G9PUV.

Village walk - NOT amateur radio


Yesterday we went on a walk around the village. The collage shows some of the things we saw