An evening of FT8 on the 40m Band

I spent the evening/early morning trying some FT8 on the 40m band taking advantage of the grey line and night time propagation. It’s been a while since I’ve stayed up late to catch some DX on 40m and it brought back memories of the all nighters I used to do when I was on air as F5VKM in France.

The 40m band has always been one of my favourites, there’s always great DX to be had when the band is open and on the grey line the world really is your oyster.

I’ve always been a huge fan of CW on 40m, there are some great seasoned op’s on the band and it’s always a real pleasure to QSO with them on the key. This time I decided to see what could be achieved with FT8 and 22w of power from my Yaesu FTDX10, a combination that should give me global reach.

Setting up at just past 6pm on May 9th 2022 the band was already busy with European stations, lots of them! There was no room to squeeze in and call CQ, the FT8 section of the band was packed with signals filling the allocation completely with many calling over the top of each other.

I decided to take my normal stance of search and pounce to get the stations I want to work rather than just working the masses endlessly.

I initially worked a bunch of Russian stations ranging from 1200 to 2200 miles out, good distances were easily achievable even though we were still in full daylight.

My home-brew multi-band vertical antenna worked well on 40m

In amongst the throng of FT8 stations I spotted UN3P, Vladimir in Karaganda Kazakhstan, not a country I have worked a lot since getting back on air and at 3013 miles it’s a good distance to achieve on 40m whilst still in broad daylight.

I gave a call to his CQ and he came straight back with an SNR report of -20dB, I sent him a report of -12dB so there was some 8dB difference between us. Considering I was only using 22w of power in broad daylight I was happy with the report. Of course I’ve no idea how much power he was using but, my signal was 6.63mW/Mile, not the lowest I ever had but, not the biggest either.

I worked a bunch more RA9/UB9 stations in the 2000-3000 mile range and then started hearing the Australian stations on the early grey line. Initially their signals were suffering some deep QSB but, it wasn’t long until their signals were constant and stable.

All the stations that heard M0AWS 09/05/22 – 10/05/22 on 40m

Ian, VK3VDX in Victoria was the first station from Oz in the log at -19dB/-20dB, pretty even SNR reports. At 10451 miles it equates to 2.10mW/Mile.

Closely following was John, VK5PO in Mallala South Australia, much stronger signals this time at -10dB/-14dB, 2.19mW/mile over a total distance of 10028 miles.

VK5PO Mallala South Australia

As darkness replaced light the propagation swung west with east coast USA and Canadian stations dropping in to the East coast of the U.K.

John, VO1BE was the first north American station in the log with -1dB/+1dB SNR reports. To be +1dB in Canada with just 22w really is quite impressive. I’m guessing he has a very low background noise level.

I worked a bunch of East Coast USA stations and then PY2GZ popped up on the waterfall. From my QTH I have a clear view South East to South West across flat ground for miles and so it’s normally pretty easy to work stations in that zone and this evening was no different. First call was answered and -10dB/-17dB SNR reports were exchanged, 3.68mW/mile over 5965 miles.

My 14.81m tall home brew vertical works superbly on the 40m band with tuning handled by my CG3000 Remote Auto Tuner. This is actually my 30m band EFHW vertical antenna but, removing the 49:1 Unun and replacing it with the CG3000 has made this antenna much more versatile.

CG3000 Remote Auto Tuner connected to the 14.81m vertical antenna and ground system

The next station in the log was BG0BBB in Xinjiang China with -9dB/-18dB SNR reports exchanged. China is always a hard location for me to get into for some reason so, I was glad to get another Chinese HAM into the log.

BG0BBB Xinjiang China

As the propagation started to swing westerly I got 8P4JP in Bridgetown Barbados into the log. It took a few calls to get the exchange completed due to very deep QSB between us but, with some perseverance the contact was completed successfully and I had a new one in the log!

I continued to work a flurry of East Coast USA, Brazilian and Puerto Ricon stations one after the other until suddenly stations from the east started coming in again.

First from the east was Igor, 4L1FL from Tbilisi Georgia, another new one for me that somehow seems to escape me every time I come across Georgian stations on the bands.

4L1FL Tbilisi Georgia

UN7JO in Ust-Kamenogorsk Kazakhstan was loud with me at -5dB SNR although I only got -21dB SNR back, some 16dB difference across the path of 3386 Miles.

One station of particular interest was VY0MEL, Julien in Rankin Inlet, Nunavut Northern Canada. This is the most northern Canadian station I’ve worked in a long time and it was great to get him in the log. His QRZ page is worth a read, he works at a mine in Nunavut on a 14 day rotation and so has a fair bit of time for HAM radio. Using just a dipole that is strung between two shipping containers and only 60cm above the snow in the centre he was a good signal at -19dB here in the U.K, especially considering he was still in broad daylight.

VY0MEL Rankin Inlet, Nunavut Northern Canada

Needless to say I had a fun filled evening/early morning on the 40m band, once again it didn’t disappoint and I got a couple of new countries in the log. I think the next late night will have to be a CW evening on 40m to see how well I do in comparison.

The full list of stations worked over 9th-10th May 2022 using FT8 on the 40m band can be viewed in my WSJT-X log in glorious technicolour with distances and mW/mile figures for every contact.

Map showing all FT4/FT8 stations worked up to 10/05/22 all bands

More soon …

Searching the WSJT-X log whilst on air

searchwsjtxlog v0.4 showing search for partial callsign

Being a UNIX/Linux command line guy I’m not a fan of a lot of these GUI based logging programs that are full of functionality I’ll never use. I currently have RumLogNG for the MacBook Pro but, I really don’t like it. It does many things I don’t need and not the things I really need when on air.

So I decided to write a bunch of command line based programs that do exactly what I want with minimal fuss. The first of these programs was adi2html, a simple program that converts the WSJT-X ADI log file into HTML so I can easily put it on my website.

I’ve now written a new program using the same BASH shell technique to allow me to search the WSJT-X log file quickly and easily whilst on air.

searchwsjtxlog is a simple little shell script that searches for either a full or partial callsign and presents the results instantly. I use this script a lot when working FT4/8 as I can see if I’ve worked a station before and on what bands easily and quickly.

The script works on Linux and MacOS Big Sur (Not got Monterey to test but, should work fine). If you find a bug please let me know and I’ll fix it as soon as possible.

Note: Since MacOS uses such an old version of the BASH it cannot handle spaces in the path to the wsjtx_log.adi file. On MacOS you’ll need to create a softlink to the file and then put the path to the soft link into the script for it to work properly. CD into the directory where you have saved the searchwsjtxlog.sh file and then run the following command:

ln -s /Users/YOURUSERNAME/Library/Application\ Support/WSJT-X/wsjtx_log.adi ./wsjtx_log.adi

Make sure you replace YOURUSERNAME with your MacOS username. The command is all on one line and not on two lines as shown above.

You can download v0.4 of searchwsjtxlog using the link below.



More soon …

160m Band NVIS Antenna Experiment

Following on from the 80m Band NVIS Antenna Experiment I spent some time using the same setup on the 160m band.

To recap, the NVIS antenna is a 30m long end-fed wire that is between 3 and 4m above the ground over it’s entire length. This is the longest wire I could get into my tiny U.K. garden and so I wanted to see what was really possible with such a low short wire on the low bands. My goal was to get good Inter-G signals so that I could chat with other U.K. and close European stations during the summer months. The tuning is done automatically by the CG3000 remote ATU I picked up very cheaply on Ebay.

Having very anti-antenna neighbours I have to tread carefully not to upset them as I have already rattled some cages having the 20m EFHW Vertical on an extending fibre glass pole at the end of the garden overlooking the farmers field.

The CG3000 remote ATU matches the 30m wire nicely on the 160m band with an SWR of less than 1.2:1 across the entire band with multiple retunes. It’s certainly very convenient to have such a setup.

Setting the power output on the radio to 25w which is the maximum I use for FT4/FT8 on the Yaesu FTDX10 I started WSJT-X and waited to see what I could hear. With the background noise swinging between S7-9 most of the time I was surprised at how many stations were being decoded. Some of the stations were barely visible on the waterfall but, I got consistent reliable decodes.

Stations heard during a 1 hour period on 160m NVIS Antenna Experiment

As you can see on the map above I was hearing stations from all over Europe and well into Russia. There certainly isn’t the proliferation of stations on the 160m band that there are on the 40m band but, there were enough for me to get some good results.

It was nice to reliably copy some U.K. stations on 160m FT8 even though I didn’t hear a single SSB station on the band.

Map showing stations that heard M0AWS on 160m during the NVIS Antenna Experiment

Over a period of about 3.5 hours I was heard by a good number of European stations but, wasn’t able to work all that I heard as I was struggling to compete with the much more powerful stations. Limiting my transmit power to 25w to protect the PA on the radio does tend to limit my success at getting through to stations at times but, I am a firm believer in being able to hear better than I can shout, especially on the low bands.

Map showing all stations worked during the 160m NVIS Antenna Experiment

Over the test period I didn’t work a huge number of stations but, I did manage to work stations over a large area of Europe with the best distance being 1004 Miles into Finland, much further than I ever thought would be possible with such a simple setup.

I’m sure that when the band is in better shape with lower noise levels and better propagation the antenna will post probably perform better but, it’s certainly proved it can do the short hop NVIS comms that I was looking for.

I have designed a new NVIS antenna for the garden which manages to incorporate considerably more wire into the same space that is resonant on the 80m band. With the CG3000 remote ATU it should tune up well on 40m-160m and give much better results. This design does require a 10m fibre glass expending pole which I need to purchase before I can erect it in the garden. I’ll get all the information for the design onto the Antenna section of the website soon.

So to summarise, a 30m end-fed wire at between 3 and 4m above the ground will give good NVIS results on 40m-160m with a very low visual impact. For those like me that have a small garden, a simple antenna like this is much better than no antenna at all.

More soon …

80m Band NVIS Antenna Experiment

Following on from my 40m band NVIS antenna experiment I ran the same series of tests on the 80m band to see how well the NVIS antenna works.

Being only 30m long the antenna isn’t very well suited to the low bands but, with the tiny garden we have here in the U.K. and the anti-antenna neighbours it’s the best I can do.

I started off looking for SSB contacts only to find no one on the band. I eventually found G8MNY calling CQ from Croydon south of London. He was a huge 5/9+20db with me so I was hopeful that he’d hear me.

Tuning up the antenna on 3.710Mhz and setting the O/P to 40w I gave him a call and got an immediate response. We ended up chatting for around 30mins with ease, the band wasn’t too noisy and Jon was running 400w so he was a solid signal with me. My 40w got me a 5/8 report which I was very happy with.

Once we cleared I tuned around the band and even called CQ a few times, but there was nothing to be heard.

I went and had something to eat and then returned to the shack before the greyline, the band was a little more lively and so I switched over to FT8 mode and started working stations.

Stations initially heard on FT8 whilst still in daylight

I was really quite surprised how many stations I could hear and make contact with even though I was still in daylight. The effect of the greyline really is quite pronounced.

Stations that heard me on FT8 whilst still in daylight

I was being heard by a good number of continental stations even though I was still in daylight. Signal strengths were good and I was soon working stations one after another with ease.

As the night drew closer and the U.K. moved into darkness stations further east started appearing on the WSJT-X window and I was surprised how many I was able to work considering how low and short the antenna is for this band.

German stations were always the strongest throughout the test which is to be expected with an NVIS antenna as they are just across the north sea as the crow flies.

Map showing all stations heard on FT8 during 80m NVIS antenna experiment

By the end of the evening I’d heard a good number of stations with the most distant being north of the Kazakhstan/Mongolian border as shown on the map above.

All stations that heard M0AWS on FT8 throughout the NVIS antenna experiment

I was pleasantly surprised at how many stations were hearing me throughout the test, getting as far south as the islands off the coast of north Africa and well into Russia was amazing for a horizontal antenna that is only 4m-5m above the ground.

Map of all stations worked during the 80m NVIS antenna experiment

The number of contacts was nowhere near as prolific as during the 40m experiment mainly due to the fact that the band wasn’t as busy however, the contact pattern was very similar to that on 40m with the most distant station being R2EA/P just south east of Moscow at 1544 miles.

European coverage was very good but, sadly I didn’t hear many U.K. stations and so I’m not sure how well my Inter-G coverage will be. Perhaps another test during the day when conditions are better will shed some more light on this.

Overall I’m very happy with the antenna performance on the 80m band, it’ll certainly be ideal for European chat during the summer months and hopefully inter-G will be good too.

Next will be a test on 160m, this could be interesting!

More soon …

40m Band NVIS Antenna Experiment

Since setting up the new station at my U.K. QTH I’ve not had any Inter-G contacts. This has mainly been due to the fact that the antennas I’ve currently got in place are all designed for chasing DX and so have far too low a radiation angle to be able to talk to other U.K. stations.

One of the things I do like about radio is the local chatter on the low bands. In the summer months working Inter-G on the low bands is most enjoyable so, I decided to put up a simple Near Vertical Incident Skywave (NVIS) antenna ready for the summer.

Unlike my French QTH, here in Suffolk we only have a tiny garden and so it’s a challenge to get any length of wire up that is anywhere near long enough for the low bands.

A quick measuring of the garden I worked out I could get 30m of wire approximately 3-4m off the ground at best. I’m very aware of my anti-antenna neighbours and so it needs to be as stealthy as possible.

I decided to use some 1.5mm wire that I had in the workshop and utilise the high washing line poles that are already in place to get the wire along the max length of the garden.

With the wire in place and connected to the CG3000 auto remote tuner that I got off of Ebay for a song, ground post and radials connected I found that the antenna tunes up fine on all 3 low bands, perfect!

Tuning up on the 40m band I had an SWR 1:1 anywhere on the band. I could hear a number of strong U.K. stations and a few Dutch and German stations too. Since I’m on the East Coast of the U.K. The Netherlands and Germany aren’t that far away as the crow flies.

Setting the radio onto 40w SSB (First time on SSB in a very long time!) I put out a call. First station to come back was G8VVY, Robin in Malmesbury Wiltshire. Signals weren’t particularly strong and I gave him a 4/4 report and got a 5/5 in return.

Next station was PA3GLK, Dave in The Netherlands. Again signal reports were 5/5 and 5/6 but, perfectly readable.

Next up was G0SXC, Kevin in Lancashire. Signal reports were 5/9 both ways this time, very strong and fully quietening, the high angle radiation was doing its thing!

Last call was ON3PAT, Pat in Belgium. Very strong signals both ways, 5/9++ at a distance of 153 miles. NVIS propagation is working very well. I turned the output down to just 25w and Pat still gave me a 5/9 report.

Later in the day I decided to run some FT8 QSOs on 40m to see how far I could get reliably with no more than 25w. I was hoping that I may just be able to get 1000 miles as an absolute maximum but, be able to work stations at 100 Miles or less with ease.

Map showing NVIS FT8 contacts on the 40m band

As you can see on the map above, 1534 miles was the best achieved, RX3ASQ just east of Moscow. The thing that pleased me most was the number of U.K. stations I could hear with the closest being just 43 miles away. Most European stations were easily worked even with reduced levels of power (10w) and so I’m hoping that this simple end fed NVIS antenna will become my goto antenna for local chatter on the 40m band.

What was very interesting was what I could hear on the antenna, I didn’t expect to hear any DX stations at all however, I was surprised to see stations from Mongolia, Japan and the USA popping up in the WSJT-X window.

Obviously I couldn’t get back to them as my angle of radiation was far too high to get a signal out over those distances but, it just goes to show what can be a heard on a very low long wire.

Map showing stations heard on 40m using NVIS antenna

By the end of the evening to my surprise I had been heard in the USA, I was amazed to see where I’d managed to get into with such a low antenna. The main cluster of stations were in the U.K. and Europe of course which is exactly what I wanted from this antenna.

Stations that heard M0AWS on 40m FT8 using NVIS antenna

So the next test will be on the 80m band, I’m hoping to get similar results on SSB with inter-G stations being easy to work. I doubt I will be able to get anywhere near the 1500 miles I achieved on the 40m band but, I’ll be more than happy with U.K. and EU stations.

More soon …

adi2html v0.6 release

Following on from the adi2html v0.5 release I’ve now added a little more code to include a map of the contacts detailed in the wsjtx_log.adi file so that there is a visual representation of the data included in the webpage. (Map must be generated externally and JPEG/GIF/PNG uploaded to website to be included in the webpage).

See my WSJT-X log here

Just to recap, adi2html generates a HTML webpage from the wsjtx_log.adi file so that the log can be presented in a palatable format on a website.

As before the code can be downloaded using the link below.

If you use my code please consider leaving the footer in place so I get some credit, thanks!

Falklands Calling …

When I lived in France (F5VKM) I was totally focused on the low bands. I spent years trying to get the Falkland Islands on 160m. Now living in the UK with a typical small garden I no longer have the luxury of big antennas. Currently I’ve just got my EFHW Vertical for 20m at the end of the garden.

Today I heard the Falkland Islands on 20m for the first time since setting up the new station, I was amazed to say the least.

WSJT-X FT8 working VP8VK with just 25w

I decided to give the two stations a call, didn’t get an answer from VP8ADR but, VP8VK then popped up and I snuck in and got a quick QSO with just 25w.

FT8 QSO with VP8VK

Working DX is so much easier on 20m than it is on 160m, I’m amazed!

-23dB is very close to the limit for FT8 but, it was enough to get a complete QSO and the Falklands in the log.

I also got VK6AS on 20m FT8 today, again with just 25w. This EFHW Vertical for 20m really is an excellent DX antenna, it’s perfect for the small garden too!

All stations heard FT8 20m

More soon …

FTDX10, Apple Computers and the USB Audio Chain

One of the things I’ve had issues with ever since purchasing the Yaesu FTDX10 transceiver is control of the audio chain via the USB connection on the rear of the radio.

The output from the radio into my Macbook Pro is just too high, WSJT-X is constantly pushed beyond the green zone and often into the red zone when monitoring FT8 signals with the AGC off. The only way to cure this is to keep the AGC on Auto which sometimes results in not hearing the very weak DX stations due to the AGC not reacting fast enough. Putting the AGC on fast causes the red line to be hit far too often once more.

Sadly, the USB Audio Codec doesn’t provide any volume adjustment on audio coming from the radio into the MacBook Pro thus, it’s just full volume all the way. This is a flaw in the codec design and really does need to be resolved long term.

Looking at the audio going the other way, that is from the MacBook Pro into the radio via the USB port fortunately there are gain controls available both on the MacBook Pro and on the radio itself.

Ever since venturing into the world of WSJT-X & FT8/4 I’ve had an issue with only being able to move the PWR slider in the WSJT-X up to the first marker at the bottom of the screen, anymore and the ALC on the radio goes off the scale instantly!

So yesterday I decided to investigate the audio chain into the radio more thoroughly and see what could be done about the levels.

Looking at the radio manual I found that there is an RPORT GAIN setting in the menu system that can be used to alter the amount of gain applied to the incoming audio signal on the USB port in the radio.

FTDX10 Rport Gain entry in the manual

As detailed in the manual, the default setting for this is 50 in a range of 0 to 100. So that’s a 50% increase in gain applied to the incoming audio at the radio end, that’s quite a boost! (The gain is applied both in SSB and Data Modes)

I decided to experiment reducing this figure to see if it gave me greater control over the audio output from WSJT-X via the PWR control. This did indeed help however, there was still too much audio coming into the radio from the MacBook Pro and so I needed to look further along the audio chain.

Moving back onto the MacBook I opened the Midi App and took at look at the Output controls for the USB Audio Codec, sure enough this was set to max for both channels, not good.

Reducing the levels in the midi app started to make much more of a difference, I could now raise the audio level using the PWR control in WSJT-X without things immediately going wild and could now control the levels with a far greater level of granularity than ever before.

After much tinkering I eventually found the levels whereby I could drive the rig to the selected output power (20w) without the ALC going off the scale and the signal becoming horribly distorted, there was calm in my audio chain once more.

So what settings did I settle on?

On the radio itself I wound down the RPORT GAIN setting from 50 to 20, this reduced the amount of gain applied to the audio coming in on the USB port considerably and helped to tidy up the FT8 signal.

FTDX10 RPORT GAIN Setting reduced from 50 to 20

It’s great that there is the facility on the radio to reduce the gain on the inbound audio signal, if only Yaesu would do the same for the outbound audio level.

Next, on my MacBook Pro via the Midi app I reduced the output level on the USB Audio Codec from the default maximum down to 0.494 (-19). This stops the audio level from being too high going into the radio and removes all distortion from the resulting signal.

Midi App on Macbook Pro showing reduced audio output

Once these small changes have been made it becomes necessary to raise the PWR level in the WSJT-X app to roughly the centre position. At this point the radio gets a clean, distortion free audio input whilst driving the radio to the full 20w output with no movement on the ALC whatsoever.

I found I could move anywhere on the frequency spectrum on FT8 without any of the levels changing and with the ALC not moving whilst the radio delivered the full 20w output.

I also checked FT4 mode as it is an MFSK mode to see if these settings worked for it too and I’m glad to say it worked perfectly! (I also found I really liked FT4!)

WSJT-X with the PWR setting at roughly 50%

Altering the PWR level in WSJT-X doesn’t have the huge effect it had before and now it’s very easy to adjust the level without the ALC going off the scale in an instant.

It took me about an hour or so to get this just right but, it was well worth the time invested.

I hope this is of use to other Apple Mac computer users in the HAM community.

More soon …

adi2html v0.5 release

Following on from my original article where I detailed the adi2html Bash script that reads in the WSJT-X log and creates an HTML version of the data so that it can be presented in a palatable format on websites (See my WSJT-X log here), I’ve now released v0.5 for public consumption.

In adi2html v0.5 I’ve added colour to the webpage that is generated to make it easier on the eyes and rewritten the function process_log() so that it uses the column name to identify each field instead of the row position.

By making this change it should cope just fine if the order of the fields is ever altered in the WSJT-X log during its development.

As before the code can be downloaded using the link below.

If you use my code please consider leaving the footer in place so I get some credit, thanks!

Create HTML webpage from wsjtx_log.adi file

I had some spare time today so I finished a small BASH program that I started writing yesterday that reads the wsjtx_log.adi file and writes the data out in HTML format so that it can be incorporated into my website (See the Logs Menu).

(Sorry the font is so small but WordPress is crap at displaying code!)

It’s a fairly simple piece of code that anyone who is into Linux and has a basic understanding of the BASH shell will easily be able to comprehend. (Yes there’s a little awk and sed in it just to add to the entertainment value!).

There are a few places where the code can be improved which I’ll address in v0.3 when I have time but, for now I’ll put it online just incase anyone is interested in using it.

If you do use the code please consider leaving the footer in place so I get some credit.

More soon …