Although I have never used these, they seem a good idea. As I understand it, interference and RF can travel back to the rig on the coax outer. In some cases this can mess up the SWR reading, add to RX noise and cause RF burns. So the idea is to choke off these with a line isolator. Presumably clip on ferrite beads might make a difference. The basic idea is to choke off RF currents flowing on the coax outer whilst leaving the inner untouched.
26 Apr 2021
25 Apr 2021
10FT8R schematic - my apologies
This weekend I was intending to put the schematic of my 10m FT8 RX on this blog. Sadly, I had no time. The weather was dry so I was gardening.
Hopefully it will be up within the next few days. Please accept my apologies. If I had found my SPlan CD I could have done it. I have to master a new tool first!
Ickworth Lambs - NOT amateur radio
Ickworth is a National Trust property with extensive grounds.
10m Phaser SSB transceiver
This kit is on order, but it has not yet arrived. It is a 4W SSB rig for 10m FT8.
It should fit my needs well freeing up the "big rig" for other things. It was designed by Dave Benson K1SWL, so should be good. SMA parts are already fitted.
4W FT8 on 10m will get me worldwide QSOs.
More blossom - NOT amateur radio
This is the causeway in Burwell, a route used centuries ago by monks walking to Ely Cathedral.
Connecting the IC-705 to the shack PC
Later I hope to download some USB drivers allowing me to connect the IC-705 and the PC. This should allow CAT rig control and audio connections. I hope to try FT8 later. As a precaution I shall choke the cable.
Up to now I have taken small steps only. Getting FT8 to work with the IC-705 would be great.
10FT8R on again
As yesterday, I have got the 10FT8 10m FT8 RX connected to the indoor loop again today. So, I am monitoring 10m FT8 all day. No spots as yet at 0854z.
UPDATE 1825z: No 10m FT8 spots today. Unless there is a brief late opening, I am probably going to spot nobody today. I definitely need a better antenna!
Ephemeral - NOT amateur radio
24 Apr 2021
Ickworth - NOT amateur radio
It is famous for its rotunda. The grounds are extensive.
Getting the 10FT8R on the right frequency
Earlier posts show the 10FT8R 10m FT8 RX works as expected. It is spotting a similar number of stations to those spotted on my FT817ND with the tiny indoor loop. With a "proper" 10m antenna outside, I am sure many more would be copied. At a guess I would say my loop is at least 6dB worse than a dipole outside. It is also quite directional. As soon as my son can help, I shall get a wire dipole erected.
One issue I had was how do I net it without a frequency counter? This is the method I used. I set up the "big rig" on 10m FT8 with WSJT-X but set the frequency to 28.073MHz rather than 28.074MHz. I then adjusted the oscillator frequency until I spotted a faint signal at 1kHz audio. Voila!
Simple. Lots of stations spotted today.
Modulation sounds
Sometimes you may wonder what various sorts of modulation actually sound like. This website may help you identify some.
See https://mynoise.net/NoiseMachines/amateurRadioNoiseGenerator.php
Morning walk - NOT amateur radio
More on the 10FT8R 10m FT8 RX
A few moments ago UA2FBW (1365km) was spotted on the 10FT8R RX with the indoor loop. The RX is on all day. It certainly works! His signal was strong.
UPDATE 1205z: 18 stations spotted on RX so far. The 10FT8R is obviously working on the small indoor loop antenna!UPDATE 1340z: 21 stations so far spotted on RX with the 10FT8R and the tiny indoor loop antenna. As far as I can tell, it is very similar to the FT817ND on RX. All spots so far look like Es.
UPDATE 2045z: QRT. All gear off.
SPlan circuit diagram alternatives?
Years ago I was given a free copy of SPlan to enable me to draw circuit diagrams for GQRP SPRAT. I have no idea where this is! Buying SPlan 7.0 costs 49 Euros. which I do not want to pay.
Does anyone know of a free circuit diagram program that is easy to use please?
At the moment I have only one schematic to do (the 10FT8R).
I thought SPlan was on a CD.
23 Apr 2021
10FT8R RX working!
I had a few problems getting the crystal pulled down enough, but a small inductor in series with the crystal did the trick. I shall tell you how I netted the crystal in another post.
So far, ES2AJ (1716km) has been spotted using just the indoor loop at -12dB S/N, which is strong. This means the "big rig" does not have to be tied up when monitoring 10m FT8.
In the end I started with my WISPY RX which I found. The sharp eyed may notice an unused oscillator buffer which can be removed from the board. A simple PCB could be made if this was ever a club project.
All being well, I shall publish the circuit over the weekend.
Post Office cock-up - NOT amateur radio
Years after a faulty computer system (Horizon) resulted in hundreds of sub-postmasters being prosecuted for fraud (some were imprisoned, went bankrupt or lost homes), some have had their convictions quashed.
I hope those in charge at the time are sent to prison. Why should so many innocent people suffer for the total ineptness of those in charge? Some sub-postmasters have died and some have lost marriages.
This was a cock-up on a monumental scale. You are not telling me someone at the top didn't smell a rat when so many were being convicted of fraud? At the very least this is gross incompetence. At worse, it was a cover-up.
Heads MUST roll!!
10FT8R progress
It is nearly finished, but I was unable to pull the 14.040MHz crystals low enough, so I shall have to modify the oscillator slightly when we get back, as we are going out this morning.
I can get within 700Hz with just capacitance in series, but I shall have to add a little inductance too. I was hoping to stick this RX on when out, but I shall have to wait. At least it oscillates!
Reactive or proactive? - NOT amateur radio
The UK government amazes me by how totally STUPID it is at times!! It is only now that hotel quarantine is mandatory for travellers from India.
We have known about the problems in India for days and in the meantime lots of travellers have returned, potentially spreading deadly new variants to other adults and children who can spread it still further.
Why did we not impose an immediate ban on Indian flights or at the very least mandatory hotel quarantine, at least for now, as a precaution? This (in)action beggars belief. Some times I am flabbergasted by how stupid we can be!
Dalham - NOT amateur radio
Canadian 472kHz transverter
See https://sites.google.com/site/g3xbmqrp3/mflf/472khz_tvtr
Parsonage Farm - NOT amateur radio
22 Apr 2021
Climate change - NOT amateur radio
"It is much easier to set targets than take action to meet them. "
Personally, I suspect the world will "wake up" when it realises that green energy can actually be lower in cost than fossil fuels and can create jobs.
This is especially true if investment is switched to renewable energy rather than fossil fuels. The main breakthrough needed is low cost storage of renewable energies like wind and solar. This would be an absolute game changer.
I hope we wake up soon enough.
Look at TVs and cameras. 20 years ago who would have envisaged TFT screens and digital cameras? In 20 years from now we will probably look back and think, "did people really drive cars powered by petrol and diesel?".
One thing the Covid-19 pandemic has taught us all is just how well we can communicate without travelling. I suspect more of us with use things like Zoom for meetings rather than travelling for hours by plane, train or car. I also suspect that people will work from home more, maybe Mondays and Fridays and go into offices less often. We will still have offices and shops, but fewer. More of us will shop online.
Changes are coming.
See https://www.bbc.co.uk/news/science-environment-56837927 .
Potholes in roads - NOT amateur radio
If these are dangerous, many get filled in fairly quickly so the local authority does not get sued for the damages caused.
We have had a cold and wet winter. I also suspect that the workmanship last year could have been better and many filled-in potholes would have survived. A classic case of save a few pennies in the short term, but spend much more in the longer term.
6m FT8 QRP (Thursday)
 |
| V2000 Vertical |
UPDATE 1324z: 5 stations have spotted my 2.5W 6m QRP FT8 TX. I have spotted 49 stations in 8 countries on 6m FT8 RX.
UPDATE 2100z: 58 stations spotted on RX and 5 stations have spotted my QRP TX.
Spring afternoon - NOT amateur radio
We had just returned from tea in a friend's garden. Nice to visit someone again!
6m FT8
Disappointed with the Lyrids. I stayed on 6m FT8 RX overnight but spotted nothing new. Either FT8 was the wrong mode to use or there were few meteors.
UPDATE 0847z: Puzzling. I just resynced to internet time so the internet must be working. Two stations recently spotted did not appear on PSKreporter. Do they have a problem at their end?
UPDATE 0855z: All now working. Not sure what was happening, but 9 stations just spotted and on PSKreporter. Furthermost OE9KFV (855km).
IC-705 features
Every day, I seem to discover something new. It seems that now there is an SD card inserted it records both RX and TX. Imagine my surprise when I could play the East Cambs Net from last Monday.
My USB-C lead has come so I hope to try FT8 in the coming days. No doubt there will be some surprises there too!
21 Apr 2021
Lyrids MS on 6m
The next few days sees the peak of the Lyrids MS shower. I am not sure which mode is the best for MS on 6m.
FT8 was chosen and I shall remain on 6m FT8 RX overnight using the FT817ND and V2000 vertical omni. Within a few minutes several stations were spotted with the furthermost EI4DA (578km), although I am not sure of the propagation mechanism.
See https://www.independent.co.uk/space/lyrid-meteor-shower-2021-tonight-b1835168.html
Trains - NOT amateur radio
The English love their steam trains! There are quite a few preserved steam railways in the UK.
2m RSGB activity contest results published
Once a month the RSGB organises a 2m activity contest (UKAC) on Tuesday evenings lasting up to 2.5 hours. I usually manage an hour with my QRP, omni antenna and poor voice. Results have just been published for the year including the April session.
See https://www.rsgbcc.org/cgi-bin/vhfresults.pl?Contest=144MHz%20UKAC&year=2021
Salcombe - NOT amateur radio
This is where I grew up until the age of 10. The photo was taken about 60 years ago when there were fewer boats belonging to visitors.
Inter G on 10m
Many years ago, the RSGB ran a competition in the quiet years on 10m in the evenings. Even with 10W SSB and a low dipole, I was regularly able to work stations nearly 200km away. With more power, better antennas and modes like FT8 these sort of distances should be easy.
With 4W of FM and a CB vertical 30km was possible to other locals.
What I am saying is do not neglect 10m when there is no DX around. We have plenty of space and much of the time it is under-used.
10m FT8 QRP (Wednesday)
At about 0914z, I turned on my 10m QRP FT8 with 2.5W and the tiny indoor loop antenna. G0FWX (160km) copied immediately.
I have gone back to the thinner loop wire as I was a bit concerned that the higher RF voltages with the copper pipe inductor, although higher Q and more efficient, could have damaged the matching parts on TX.
UPDATE 1308z: 3 stations spotted with the furthermost OH6EJD (1874km). Nobody has spotted me. I think this is Es.
10FT8R 10m FT8 RX
With a bit of luck, I may have this working by the weekend. It is a DSB RX for 10m FT8. It means the "big rig" can be used for other things and 10m FT8 can be continuously monitored.
Subscribe to:
Comments (Atom)
