Saturday, September 28, 2019

Tropo path opens on 2m from the UK to Cape Verde Islands - Sat 28th Sept 2019

Just a quick post to say that D41CV in the Cape Verde Islands managed to work G7RAU in the SW of England on FT8 on 144 MHz this morning, Saturday 28th Sept 2019.

The tropo forecast doesn't look great at the northern end of the path but it might be worth checking.

See F5LEN's website.

Thursday, September 19, 2019

Opening on 144 MHz from the Azores results in several contacts over 3,000kms

On the evening of the 14th and the morning of the 15th of September 2019, there was a very good tropo opening on 144 MHz from the Azore Islands in the Atlantic Ocean to parts of the UK, France, Netherlands, Belgium and Germany.

A list of the stations worked by José CU3EQ using the digital FT8 mode is shown below...

Saturday 14th September 2019
20190914 18:30 G7RAU IN79JX JT65 -18 -10 2138km
20190914 18:47 G4LOH IO70JC FT8 -02 +01 2145km
20190914 18:54 F6DBI IN88IJ FT8 -16 -16 2193km
20190914 19:47 ON4KHG JO10XO FT8 -24 -16 2768km
20190914 20:39 F6KHM IN78RJ FT8 -20 -21 2107km
20190914 20:46 GW0KZG IO71LW FT8 -16 -09 2257km
20190914 22:12 G4RRA IO80BS FT8 -19 -23 2263km
20190914 22:15 G4KWQ IO92AQ FT8 +03 +05 2480km
20190914 22:49 M0JDK IO93KH FT8 -24 -19 2563km
20190914 22:57 G8VHI IO92FM FT8 -19 -21 2496km
20190914 23:17 M0CGL JO03BF FT8 -11 -19 2632km
20190914 23:19 G0GMB IO92NB FT8 -21 -19 2513km
20190914 23:20 PA2M JO21IP FT8 -14 -07 2852km
20190914 23:24 PA3FYC JO31AF FT8 -23 -21 2927km 
20190914 23:27 ON8KW JO20BW FT8 -14 -16 2790km
20190914 23:28 G4FUF JO01GN FT8 -19 2579km
20190914 23:49 PA3BIY JO22HB FT8 -24 -16 2861km

Sunday 15th September 2019
20190915 00:06 DJ6AG JO51EQ FT8 -22 -15 3231km ODX of all
20190915 00:08 G3NJV IO70JA FT8 -09 -16 2141km
20190915 00:45 ON4GG JO20AR FT8 -08 -05 2777km
20190915 00:59 PA2M JO21IP FT8 559 559 2852km
20190915 06:53 ON4IQ JO20AR FT8 -24 -04 2777km
20190915 07:10 DG1KDD JO31LE FT8 -22 -20 2988km
20190915 07:15 M0CKM IO90QT FT8 -17 -10 2472km
20190915 07:25 DF2ZC JO30RN FT8 -16 -17 3006km
20190915 07:26 ON4PS JO20KQ FT8 -12 -06 2832km
20190915 07:33 PA0JMV JO21PM FT8 -09 -13 2886km
20190915 07:34 PA5Y JO21VO FT8 -18 +04 2922km
20190915 07:35 PA3CMC JO21WI FT8 -19 -12 2920km
20190915 07:40 ON4LDP JO10UN FT8 -21 -15 2749km
20190915 07:44 G8BCG IO70RK FT8 +01 +00 2204km
20190915 08:00 PA2CHR JO32DB FT8 -15 -20 2970km
20190915 08:06 M0AFJ IO70IC FT8 -13 -03 2140km
20190915 08:36 DK4TG JO31LB FT8 -15 -21 2984km
20190915 08:54 DF1JC JO31OG FT8 -22 -11 3007km
20190915 09:12 DF6PW JO40AQ FT8 -17 -08 3049km
20190915 09:13 DL6YBF JO31OX FT8 -17 -06 3027km
20190915 09:23 PA3PCV JO20VV FT8 -24 -18 2901km
20190915 09:44 PA4EME JO20WX FT8 -17 -02 2909km

This is a more detailed view of the stations worked...

Wednesday, September 18, 2019

US Government Report on 32-42 MHz from 1998

Thanks to Rob, PE9PE who sent on an interesting link recently about a US government report about the low VHF spectrum from 32 to 42 MHz.

After a bit of research, I established that the report titled "NTIA Special Publication 98-36 SPECTRUM REALLOCATION REPORT" was from February 1998.

The report looked at who the existing users were in this part of the spectrum and whether some of the frequencies could be reallocated to commercial interests.

While the full report looked at several different bands, we'll concentrate on the low VHF spectrum here.

I have included sections of interest from the report below with certain key points highlighted in bold.

It might be worth pointing out that antennas for low band VHF tend to be very large compared to those for the higher VHF and UHF bands. For example, a full size quarter wave ground plane antenna is roughly 2.5 metres on 30 MHz and 2 metres on 40 MHz.

While the report is over 20 years old, it does show that even back then there was little commercial interest in the 30 to 50 MHz spectrum.

INTRODUCTION In the previous section, the bands to be considered for reallocation for non-Federal use were identified. All of the bands being considered for reallocation are used by the Federal Government agencies, in varying degrees, to support Presidential and Congressionally mandated missions. A band-by-band assessment of these factors is presented and recommendations are made as to which bands will be included in the spectrum reallocation plan.32-33, 34-35, 36-37, 38-39, AND 40-42 MHz 

Band Usage 
The Department of Defence (DoD) uses the frequency bands between 32-42 MHz for tactical communication using the Single Channel Ground and Airborne Radio System (SINCGARS) and other land mobile radio (LMR) assets (e.g., Scope Shield II) as well as some non-tactical intra base radio functions.

Friday, September 13, 2019

Watch out for VHF path to Cape Verde Is

Just a note to say that there is a nice high pressure system over the eastern part of the Atlantic at the moment and there is a possibility of a VHF opening to Cape Verde Islands from the UK and Ireland.

As always, it's a long shot but keep an eye on the tropo prediction website of F5LEN.

Wednesday, September 4, 2019

Tom EI4DQ completes an 11 band DXCC!

Congrats to Tom EI4DQ who recently achieved an 11 band DXCC!

While a number of EI stations have 10 band DXCC, Tom is the only one to get the magic 100 countries confirmed on eleven bands.

The key difference of course is that EI4DQ has managed to get DXCC on 144 MHz (2 metres) as well primarily by bouncing signals off the moon.

It's probably no exaggeration to say that it's easier to get an 8 band DXCC from 10m-80m than it is to get DXCC on 2m!

Here is an excerpt of Tom's 11 Band DXCC journey....

On the 21st of August 2019, I finally completed my 11 band DXCC.

I had started my plan of trying to gain the 11 band DXCC goal back in March of 2015, after completing DXCC for the 2 metre and 6 metre bands. I decided it was time to try and get DXCC on the HF bands as well. 

The last time I had operated the HF bands was back around 1998. I installed various antennas for all the hf bands i.e. dipoles, verticals, loops, etc. I decided to start at the bottom i.e. 160mtr band (1.8 MHz), and work my way up to 10mtr (28 MHz).

My first 160mtr antenna was a single wire inverted L. It worked ok but I had lots of issues feeding it at the base as it had a very low impedance. I always had to use some type of tuner at the base to feed it and make it work. 

I then made a folded Marconi L antenna out of 450 ohm open wire feeder, i.e. 4x impedance transformation. Wow what a difference! 

Direct 50 ohm feed, no tuner, 1:1 vswr, and hearing and working DX much better. I also had about 60 radials down of various lengths.

I started to listen to all the 160mtr contests picking off needed DXCC both on cw and ssb and then on FT8. I also started monitoring the Reverse Beacon Network, and the DXsummet DX cluster  for any new DXCC countries that were about. I was about to install a separate receive antenna for 160mts in late 2017, but when I purchased a ICOM IC7610, its noise reducing capabilities and receive were so good that I did not need any receive antenna. I completed DXCC on 160mtr in late February of 2019. 

80mtr / 40mtr / and 30mtr DXCC were all completed by March of 2019. 20mtr and 17mtr were completed by April of 2019. 15mts was completed in June of 2019 and 10mtr was completed in July of 2019. 

All contacts were confirmed via Logbook of the World (LOTW). I could have used some of my QSL cards from previous activity in the 1970's to 1990's period when I was very active on the HF bands but chose not to do so. I also tended to only pick out stations who were in the LOTW program.

The last band 12mtr (24 MHz) was completed in August of 2019. This band was the most frustrating band to work DX! It was a pain to hear DX on 15mtr and 10mtr and sweet nothing on 12mtr. It took me 2 months just to dig out the last needed DCXX to make 100 on this band. My final total on this band was 112 DXCC but only 100 of them uploaded to LOTW. 

So at last on the 21st of August 2019, the 11 band DXCC was completed. All together it took me just over 4 years to complete the needed HF DXCC.

All my antennas are homebrew vertical dipoles, loops or verticals, modes used cw / ssb / ft8.

Now its back to 6mtr, 4mtr and 2mtr! ... Tom, EI4DQ

Monday, September 2, 2019

Study suggests 11 year Solar Cycle is “Powered By Tidal Forces of Venus, Earth, Jupiter”

I recently across this news item based on a scientific paper which was released in May of 2019. Despite the huge differences in size, the study suggests that the planetary alignment of the planets Venus, Earth and Jupiter is large enough to effect the sun and its sunspot cycle.

"As with the gravitational pull of the Moon causing tides on Earth, planets are able to displace the hot plasma on the sun’s surface. Tidal forces are strongest when there is maximum Venus-Earth-Jupiter alignment; a constellation that occurs every 11.07 years."

The lead author of the study, Frank Stefani is quoted as saying...“There is an astonishingly high level of concordance: what we see is complete parallelism with the planets over the course of 90 cycles.”

If it is true then perhaps it might allow for better computer models to be built to predict future sunspot cycles?

Not only is the solar cycle of interest for radio propagation but it is hugely relevant to the large number of satellites in orbit in terms of drag and radiation.

More info on the study in the links below...

1) Scientific Paper... A Model of a Tidally Synchronized Solar Dynamo
2) Daily Galaxy... Sun’s 11-Year Cycle –“Powered By Tidal Forces of Venus, Earth, Jupiter”

Sunday, September 1, 2019

Failure of a $14,000 antenna project

I came across this website recently which I think some readers might find of interest. It's a story of one persons antenna project in the USA which cost $14,000 and its eventual failure.

You can read it here...