Wednesday, February 24, 2021

Twitter poll suggests that one-third of those using FT8 on 144 MHz are using vertical polarization

How it all started... After listening for FT8 signals on 144 MHz for a few days, I was suprised to hear some signals that were well over 500 kms away. 

Considering I was using just a basic vertical Slim Jim half-wave antenna in the attic, I began wondering if everyone was really using horizontal polaziation as I had expected?

I began thinking about it and I came to the conclusion that even though FT8 is a weak signal mode on SSB and horizontal polarization is the norm, there must be some stations using just a simple 'white stick' dual band vertical up on their roof. 

After all, if you have limited space or you're active on many different bands, you may not be interested in getting a dedicated horizontal antenna for 144 MHz.

The Poll... I thought it might be interesting to see just how many people are using vertical polarization on 2m FT8 so I contacted Tim, GW4VXE who writes for several amateur radio publications and has over 4000 followers on Twitter.

I suggested to Tim that it might be interesting to put a poll up on Twitter just out of interest. Tim duly obliged and put the following poll up on Twitter for about a week.

Tim asked his followers if they used exclusively horizontal or vertical polarization or if they sometimes used either for FT8 on 2-metres.


Results... A total of 76 people voted and the results were...

Horizontal Polarization - 55.3%
Vertical Polarization
- 32.9% and 
Both Vertical & Horizontal - 11.8%

There are a few caveats with the results...

1) The sample size was 76. It's not huge but I think it's still enough to give a good indication.

2) The poll was just on Twitter. Whether having the poll on Facebook or some other platform would make a difference, I don't know.

3) As Tim writes for UK based radio magazines, I would assume most of his followers are from the UK as well. Would the answer be the same in Germany, elsewhere in Europe or the USA?

In Conclusion... I think the poll results show that there are a lot more people using vertical polarization on FT8 on 144 MHz than might be expected. 

If you have a radio with 2m SSB on it then try tuning to 144.174 MHz when there is high pressure about and have a listen on FT8, you might be pleasantly suprised.

Credits: My thanks to Tim, GW4VXE for conducting the poll. You can find Tim on Twitter here... https://twitter.com/gw4vxe

Tuesday, February 23, 2021

Log-Periodic Antenna from the Netherlands for 27 MHz to 100 MHz


GB Antennes is a company in the Netherlands that sells a wide range of antennas including a log-periodic antenna for the low VHF band. The model pictured above is the GB Log-Per 9elm TX 27-100MHz Custom made Antenna.

Specs...
Frequency: TX 27-100MHz
Frequency: RX 24-140MHz
Connection: 50-52 Ohm coax cable
Power: 1.5kw PEP
Gain: 5.5dbd- 7.8dBi
F / B: 15-20 dbd
Maximum SWR: 1.6: 1
Wind load: 125kph
Turning circle: 2.75m
Elements: 9
Boom: 2 x 4.65m
Boom in 3 pieces total 6 pieces
Boom connectors: 4 x
Elements: 20-16mm
Boom diameter: 30mm
Insulator pieces PVC: 7x
Pole mounting Isolator piece tree PVC: 1x
Pole mounting: 2 x 52mm pipe clamps
Mounting bolts: stainless steel
Element clamps: stainless steel
Shipping box: 1x 1.60mx0.30x0.30cm
Weight: 19kg with packaging 22kg

It seems to be a pretty rugged antenna with elements ranging from 16mm to 20mm. The antenna also weighs 19kgs!


The photo above shows where the coax cable attaches to the two parallel bars used for feeding the log periodic.


The photo above shows the choke balun that goes to the feed point. The coax is an unbalanced feeder whereas the log periodic has a balanced feed point.

This antenna should have the performance of a 3-element Yagi over most of the low VHF spectrum but that performance over tens of MHz comes at a cost. This antenna currently retails at €675.


Thanks to Rob, PE9PE for the above link.

For more information on the 8m band, visit my 40 MHz page... https://ei7gl.blogspot.com/p/40-mhz.html

Sunday, February 21, 2021

South African ZS6WAB beacon on 40.675 MHz


While most of the activity and interest in the new 8-metre amateur radio band is in Europe, it's worth remembering that since 2015, there has been a small 10 kHz allocation in South Africa which goes from 40.675 to 40.685 MHz.

Willem, ZS6WAB in South Africa operates a number of beacons on several VHF bands including one on 40.675 MHz. An old ICOM IC-706 is used for the CW beacon and the antenna is a 5-element YU7EF designed Yagi.

The 8m antenna is at the top of this stack

The map below shows the location of ZS6WAB in the NE corner of South Africa in the locator square KG46RB.

Considering that the ZS6WAB beacon in located in the NE of South Africa, it should easily be heard in the SW of the country via Sporadic-E propagation.

Outside of South Africa, it's a long way to any other potential activity area. The best path is probably via Trans-Equatorial Propagation (TEP) to Europe. Even though it's in the region of 8000 kms, the beacon will almost certainly be heard in Europe and it's just a case of getting people to listen and report it.

There is also potential multi-hop Sporadic-E paths to Western Australia and South America but again, it's a case of someone being interested enough to listen.

At the peak of the upcoming sunspot cycle, the 40 MHz beacon may well be heard quite easily on multiple continents including North America.

Even though this beacon has been operational for some time, there have been no reports of it on the DX Cluster outside of South Africa as of February 2021. Hopefully this post might encourage a few more people to have a listen.

***

The ZS6WAB beacon is also operational on 28.205 MHz, 50.025 MHz, 70.025 MHz, 144.400 MHz and 432.446 MHz.

For more information on the 8m band, visit my 40 MHz page... https://ei7gl.blogspot.com/p/40-mhz.html

Saturday, February 20, 2021

TEP contact on 144 MHz between 3A2LU and V51E - 1990-1991

At the end of 2020, I had some posts up on the blog about some remarkable 144 MHz contacts between Argentina and the Caribbean via Trans-Equatorial Propagation (TEP). Many of the contacts were in the region of 5000 kms.

The post sparked some discussion and someone mentioned a TEP contact on 144 MHz between 3A2LU in Monaco and V51E in Namibia which had taken place in the early 90's.


The path is shown above and is in the region of 7162 kms, a really impressive distance for 144 MHz.

This contact was made in pre-internet days but from what I can tell from doing a search, 3A2LU in Monaco was running 150 watts into a 15-element Yagi. Amazingly, V51E in Namibia was using an antenna for the 160m band!


The contact which was via CW would have taken place close to the peak of solar cycle 22 so conditions must have been really good.

If anyone has any additional information about this contact then please let me know.

For examples of other long distance contacts on 144 MHz, visit my 144 MHz page.

Friday, February 19, 2021

Special permission for VK6R in Australia to operate on 35 MHz & 41 MHz back around 1989

In this post, we'll go back more than 30 years to the years 1988 to 1990 which was around the time of the peak of solar cycle 22. In an issue of RadCom (journal of the RSGB) back in 1988, it carried this interesting news item...


"Graham Rogers, VK6RO, (Western Australia) has been granted an experimental licence by the Department of Communications to transmit on the spot frequencies 35.810 MHz and 4l.750 MHz for the purpose of propagation checks, particularly to ascertain the MUF (Maximum Usable Frequency) between 30 and 50MHz during the coming peak of Cycle 22. 

FM will be transmitted, probably using a six element log- periodic Yagi covering 30 to 54MHz. with an cirp of about 83waits. Proposed callsign is VK6R. Graham will look on 28885 and 28385kHz for stations to stand by for his spot frequency transmissions. He is currently looking for a suitable transmitter."

It's worth remembering that this was a time when most people didn't have the Internet or even email. To let people know of any upcoming activity or experiments, you had to hope that people actually read about it in some amateur radio magazine.

Results... I asked Graham, VK6RO about this experiment and he said that he had managed to get a loan of a commercial low-band VHF FM radio for the tests. As for the tests, he did manage to get a report from a radio amateur in Japan on 35.810 MHz that was pre-arranged. The distance for the North-South path was in the region of 7000-8000 kms.

Graham reports that the biggest problem was the lack of activity on 28.885 MHz even though it was supposed to have been the 50-MHz liaison and crossband frequency at the time. Again, remember that there were no DX-clusters at this time.

Another problem that Graham notes was that most radios weren't able to receive between 30 MHz and 50 MHz back then.


Comment... While the tests met with limited success, the 35 MHz and 41 MHz signals would most likely have been heard in Europe near  the peak of the sunspot cycle. The problem as already noted was that most radio amateurs probably weren't even aware of the tests at the time.

It's interesting though that the licensing authority in Australia at the time was willing to grant a temporary license for these frequencies. Could it happen again for say 40 MHz? 
Maybe in the 40 MHz ISM band from 40.660 MHz to 40.700 MHz?
Would other licensing authorities around the world be willing to grant similar temporary licenses for the upcoming solar cycle 25?

Link...
1) For more information on the 40 MHz band, see a list of previous posts on this page on the blog... https://ei7gl.blogspot.com/p/40-mhz.html

Thursday, February 18, 2021

Video: Yagi Antenna talk by Kent, WA5VJB

Kent, WA5VJB recently gave a talk on Yagi antenna construction and designs for the UK Microwave Society and it is now on their YouTube page.

This talk should be of interest to anyone interested in building their own Yagi antennas for the VHF and UHF bands.

The talk lasts for about 38 minutes with a short 10 minute Q&A session after it.

WA5VJB also has his own website which has antennas and equipment for the microwave bands here... https://www.wa5vjb.com/index.html

Wednesday, February 17, 2021

2020 Report for the 60-MHz EI1KNH beacon

The EI1KNH beacon on 60.013 MHz is currently the only operational 5-metre beacon in the world and has been on air since December of 2019. In this post, we'll look at how many times it was spotted on the DX Cluster in 2020.


A total of 6 stations spotted the EI1KNH beacon on 60 MHz during 2020 and the number of spots per individual were... EA3ERE (3), EI7BMB (3), F6HTJ (1), GW0GEI (1), NL8992 (2), SP7VVB (1).

As the map shows above, most were in the region of 800 to 1800kms from the beacon which is a typical distance for Sporadic-E signals at 40 MHz during the Summer season.


Note the reception report by GW0GEI in West Wales at a distance of 175 kms by tropo.

DX Cluster... If you do hear the beacon then make sure to report it on dx-clusters like DXSummit or DXMaps as some of the other clusters ignore spots for 60 MHz as they assume they're a mistake.

More information about the EI1KNH beacon can be found here... https://www.qrz.com/db/EI1KNH/

For more information on the 60 MHz band, go to this page... https://ei7gl.blogspot.com/p/60-mhz.html

Tuesday, February 16, 2021

Update on the new 144 MHz beacon on St Helena Island (ZD7)

A few days ago, I had a post about the new proposed 2m beacon for St Helena Island. Dee, ZR1DEE has very kindly sent on some additional information.


Garry, ZD7GWM is the beacon keeper and recently took delivery of  a Motorola GM340 FM radio, power supply, cables and a Diamond X700H antenna.

As of the 4th of February, the antenna still needs to be installed and then the beacon will be turned on.

More info from Dee.....  

Gary will select the beacon frequency from a list of 4 pre programmed frequencies (Channel 1: 144.475 Channel 2: 144.325 Channel 3: 144.375 Channel 4: 144.385 ) to suit .
 
Now we wait for the Diamond antenna to be erected and BEACON SWITCHED ON

* * *
Update 16th Feb 2021: Photos of the new antenna at the bottom of this post.

* * *
 
The keyer circuit is a 8 pin PIC12F675 chip fed to the input of the Motorola  GM340 FM radio



Additional information about the beacon...
Call sign of the beacon  ZD7GWM
QRG – 144.475 frequency
Grid locator IH74DB
QTH LONGWOOD ISLAND OF ST HELENA
Antenna type DIAMOND X700H
Height above sea level  545M
Height above ground  10M
Antenna direction OMNI-DIRECTIONAL
Horizontal or Vertical  VERTICAL
Power output  20 W
Keying – mode CW
Machine Generated Mode if applicable
GPS coordinated  S 15⁰ 56’ 54.68  W005⁰ 41’ 02.34 (-15.9485  -005.6840 )
Beacon status activated soon
Beacon Keeper GARRY MERCURY ZD7GWM

Analysis... Let's have a look at where St Helena is and who is likely to hear this beacon.

Video: Amateur radio construction with Steve Hartley, G0FUW and Pete Juliano, N6QW

 A video titled 'Amateur radio construction with Steve Hartley, G0FUW and Pete Juliano, N6QW' was recently posted on YouTube by the RSGB as part of their ongoing Today at 8 talk series.

The first part of the talk (1:09 to 35:30) is by Steve, G0FUW as he introduces the subject of making your own radios and circuits. This section is aimed at beginners and is a good place to start.

The second part of the talk from 35:30 to 1:17:00 by Pete, N6QW covers more advanced designs and is aimed at more experienced experimenters.

The Q&A session goes from 1:17:00 to 1:39:23.

Monday, February 15, 2021

Video: Starting out in Microwave Bands with Neil, G4LDR


As part of their Tonight at 8 series, the RSGB had a video presentation recently from Neil, G4LDR about getting started on the amateur radio microwave bands.

The talk itself is about 1h 15m in length and it is followed by a 20-minute Q&A session.

The video covers propagation, antennas and equipment for the amateur bands from 1.3 to 10 GHz.

Sunday, February 14, 2021

FT8 signals heard on 144 MHz - Sun 14th Feb 2021

As my 10m antenna is out of action, I spent the weekend listening for FT8 signals on 144 MHz instead.


The VHF conditions weren't great but it always amazes me that I can hear signals from over 500kms away with a simple vertical Slim-Jim antenna inside the attic of my house.

Txmtr Band Mode Distance Time (UTC)
GM0HBK 2m FT8 605 km 15:11:29
M0IOY 2m FT8 556 km 14:29:44
G7LHK 2m FT8 456 km 16:55:44
G0NWX 2m FT8 454 km 14:46:44
G4TRA 2m FT8 431 km 11:58:59
G4RRA 2m FT8 337 km 11:54:35
GW1JFV 2m FT8 229 km 22:45:33
GW4VXE 2m FT8 229 km 13:26:59
EI5IN 2m FT8 197 km 12:25:44

QRT on 28 MHz as antenna cracks...

According to an old saying 'When the wind is in the east, tis neither good for man nor beast'. Or as it turns out, it's not great for antennas either!


After several days of strong easterly winds, my 10m vertical finally snapped! It's no big deal as it was a cheap and cheerful half-wave CB antenna and I had gotten four years out of it already.

The problem was metal fatigue at the top of the bottom aluminum section. The X in the photo above shows where it split... the bottom of the antenna is still there on the mast while the rest of the antenna on the right is sticking out of a hedge.

So no more reports on 28 MHz FT8 for a while. I'll have to wait for a nice dry day and see if I'll repair or replace it.

Saturday, February 13, 2021

Video: Amateur Radio in the Falkland Islands

This video about amateur radio in the Falkland Islands was put up on YouTube in January of 2021 and features VP8EME, VP8NE and VP8LP.

Friday, February 12, 2021

2020 Report for the 40-MHz EI1KNH beacon

Back at the start of January of this year, I had a post up about how often the Danish OZ7IGY beacon on 40 MHz was reported back in 2020. In this post, we'll look at the EI1KNH beacon in Ireland which transmits on 40.013 MHz and how many times it was spotted on the DX Cluster in 2020.


A total of 26 stations spotted the EI1KNH beacon on 40 MHz during 2020 and the number of spots per individual were... 9A6W (13), CT1DDN (2), CT1HMN (1), CT2IWW (1), DG0JPM (1), DK7UK (6), DM2TT (1), DM6HK (1), EA1FBU (1), EA2US (1), EA3ERE (24), EI3GYB (6), EI7BMB (1), EI7GL (2), F1EIT (7), F4FRQ (2), F6HTJ (4), OE3EMC (6), OH3BCX (1), OH3NE (1), ON4TA (3), OZ1BNN (1), PE1ITR (2), S5/M0MPM (1), SP5XMU (1), SP7VVB (1).

As the map shows above, most were in the region of 800 to 2000kms from the beacon which is a typical distance for Sporadic-E signals at 40 MHz during the Summer season.



The EI1KNH 40 MHz beacon which is just to the south of Dublin first became operational in May of 2020.

DX Cluster... If you do hear the beacon then make sure to report it on dx-clusters like DXSummit or DXMaps as some of the other clusters ignore spots for 40 MHz as they assume they're a mistake.

More information about the EI1KNH beacon can be found here... https://www.qrz.com/db/EI1KNH/

For more information on the 40 MHz band, go to this page... https://ei7gl.blogspot.com/p/40-mhz.html

Addendum...

Video clip from Tom, SP5XMU in Poland showing reception of the EI1KNH beacon...

Thursday, February 11, 2021

New 8m beacon from Slovenia on 40.670 MHz


Update - 16th Feb 2021: The S55ZMS beacon is currently under test. The power output is 4-watts into a multi-band dipole. 

The plan is to eventually increase this to 10 watts and to move the beacon to the S53M contest location which is situated on top of a hill. A proper 40-MHz dipole is planned for the site but its exact location on the site and its orientation hasn't been finalised.

* * *

More good news for the new 8-metre amateur radio band! A new beacon in Slovenia is now operational on 40.670 MHz.

The callsign of the beacon is S55ZMS and it has an output power of 7 watts into a dipole. The transmissions are in both CW and on PI4, a digital mode designed for beacons.

The beacon is located near Bakovci in the far eastern part of Slovenia near the border with Hungary and its locator is JN86BO.

The licensing authorities first gave permission for 8m beacons in Slovenia back in June of 1998 but not  much happened at the time. This new beacon in the 40 MHz ISM band (Industrial, Scientific & Medical) is now the third operational 8m beacon in Europe joining OZ7IGY in Denmark and EI1KNH in Ireland.


The map above shows the location of the 8m beacon in Slovenia and the distances from it. It's very likely that it will be heard around Europe during the Summer months by Sporadic-E propagation. The range is likely to be in the region of 800 to 2100 kms.

The fact that the new beacon from Slovenia is also further south than the beacons in Ireland and Denmark is also significant. As we move further into solar cycle 25 and the flux rises, there will be times when 40 MHz signals will be heard much further away in places like North & South America, Africa and Asia.

It's also highly likely that the 40 MHz signal from Slovenia will be heard in South Africa through a combination of Trans-Equatorial Propagation (TEP) and Sporadic-E (Sp-E).

For more information on the 40 MHz band, visit this page on the blog... https://ei7gl.blogspot.com/p/40-mhz.html

Wednesday, February 10, 2021

Yugoslav ELTING 8000 radio for 40 MHz

If I come across any radio that will operate on the 40 MHz band, I like to keep a record of it here on the blog. One such radio is the ELTING 8000 which was a 1980's vintage radio that was built in Yugoslavia. It was also manufactured by RIZ.


This low-band VHF radio used FM modulation and had a maximum of ten crystal-controlled operating channels.


In the example shown above which is the base version, it is set up for simplex operation on 40.775 MHz, 41.220 MHz, 41.775 MHz and 42.200 MHz. The specified range of the radios was from 40.7 MHz to 42.4 MHz.


This is an internal view of the radio. The mains power supply can be seen quite clearly on the right. You can also make out the crystals just left of centre.


This is the view from the other side and as you can see, there is a second PCB.

The frequency chart below shows how the crystal frequencies were selected...

The transmit frequency is a 12th multiple of a crystal operating at about 3.5 MHz. Possibly something like X3 first, select the third harmonic and then multiply that by 4.

For this radio to operate on say 40.680 MHz (which is the centre of the 40 MHz ISM band - Industrial, Scientific, Medical), a crystal of 3.390 MHz is required for transmit.

To receive on 40.680 MHz, then a 51.380 MHz crystal is required (receive frequency plus 10.7 MHz IF).

There were several versions of the 8000 series... 1) 8000F for fixed operation, 2) 8000M for mobile and 3) 8000P for portable.


The RF output power of each one was 10 watts. There was also a hand portable version called the 8000/1.5P with a 1.5 watt output.


Some of these radios are available on the second hand market and might be a way to get going on just one select frequency on the 40 MHz band.

Links...
1) Crowave Blog

Tuesday, February 9, 2021

"Energy Island" to become a new IOTA for Denmark???

 

I was reading an interesting news article today about a new project to build a giant island off the coast of Denmark in the North Sea. It will serve as a hub for 200 giant offshore wind turbines.

The world's first energy island will be as big as 120,000sq m but there are hopes to make it as large as 460,000sq m. It is the biggest construction project in Danish history, costing an estimated 210bn kroner (£24bn; €28bn: $34bn).

IOTA... Located some 80kms or so off the Danish coast, I couldn't help thinking if it would qualify as a new IOTA reference?


The IOTA (Islands On the Air) awards programme is very popular with radio amateurs and is probably  second only to the DXCC programme in terms of popularity. I'm sure a new Danish IOTA reference would generate some interest.

Would it count though? From what I understand, it must be a certain distance offshore and 80 kms should certainly qualify. However, I think it must also be 1km in length. If it expands to its full size then it might.

Does a new large artificial island qualify as a new IOTA reference?

Update: It would seem that it won't count as a new IOTA as qualifying islands can't be man made.

VHF...  Whatever about IOTA, the new 'Energy Island' would be located out in a very wet locator square... either JO35 or JO36 and it would certainly count.


Considering how close it would be to Germany, the Netherlands and the UK, it would probably be very popular on all the VHF bands.

Noise?... While it's interesting to hear about new islands popping up out of the North Sea, it would hardly be a RF quite location with all of those inverters. Would radio communications be even possible on the HF bands? Would it even be allowed?

Monday, February 8, 2021

Video: Unusual signals heard on the VHF & UHF bands with a radio scanner

 


As radio systems gradually migrate from analogue to digital technology, more and more unusual commercial and non-commercial signals can be heard on the VHF & UHF radio bands.

Lewis M3HHY in Manchester has a very popular YouTube channel where he puts up well scripted and presented videos about a wide range of radio related subjects. He recently put up two videos about some of the digital radio signals that can be heard on the VHF & UHF bands.

Video 1... 

Signals...

1) POCSAG ...Wide area paging.
2) MPT-1327 ...Trunk radio communication networks. 
3) Commercial DMR ...digital communications.
4) Car Key Transmitters
5) TETRA ...TErrestrial TRunked RAdio
6) Temporary Traffic Lights
7) Autocab ...Radio dispatch system
8) TPMS ...Tyre Pressure Monitoring Systems
9) Multitone Paging
10) dPMR ...Digital Private Mobile Radio (446 MHz)

Video 2...

Signals...

1) FLEX ...Flexible Wide Area Paging Protocol
2) VOR ...Very High Frequency Omnidirectional Range (108-118 MHz)
3) DAB Radio ...Digital Audio Broadcast
4) DSTAR ...Digital Smart Technology for Amateur Radio
5) NXDN ...Next Generation Digital Narrowband
6) Motorola Type II ... Paging Control Channel
7) Wi-Fi ...802.11N
8) System Fusion ...Yaesu Amateur Radio Digital Mode
9) LTE ...Long Term Evolution Network (4GLT / E-UTRA - Evolved Universal Terrestrial Radio Access). Mobile phone data.
10) AFSK ...Audio Frequency Shift Keying (Paging)

For additional information on unusual signals, visit this website... https://www.sigidwiki.com/wiki/Signal_Identification_Guide

Thursday, February 4, 2021

40 MHz page has now over 10,000 pageviews

 


At the end of January 2021, the 40 MHz page on the site passed the 10,000 pageview mark.

Back in 2018, Irish radio amateurs gained access to a large part of the low VHF spectrum between 30 MHz and 50 MHz. As I went looking for information on anything to do with 40 MHz operations, I found it scattered across the net with no real central source.

In 2018, I started collecting information about low band VHF signals and equipment and in the summer of 2018, I put the 40 MHz page up on the site. This was a place where I could put links to all of the relevant posts that I had put up on the site. It also meant that anyone new starting off could go there and get all of the relevant information in one spot rather than trying to find it on the net.

As the stats above show, the page got a steady stream of traffic in 2018 and 2019 but really took off in 2020 with the increased level of interest in the band.

Link to the 40 MHz page... https://ei7gl.blogspot.com/p/40-mhz.html

Wednesday, February 3, 2021

40 MHz contacts now accepted on the eQSL platform

 


Tim, EI4GNB reports that the eQSL website is now accepting 40 MHz (8m) contacts on their platform.

Many radio amateur use this site to confirm contacts that were made on the radio and is an alternative for many to the traditional physical QSL card.


Tim also notes that while eQSL are handling 8m QSOs now, a lot of the various logging software programmes still have to catch up as they still don't recognize 8m as a valid amateur band.