Contact on the 40 MHz band in the USA between two experimental stations - 9th Jan 2022

 

9th January 2022: In the second half of 2021, a number of amateur radio stations in the USA applied for experimental permits for the 40 MHz band... see this previous post.

On the 9th of January at 04:15 UTC, WM2XEJ in Georgia managed to complete a two way FT8 contact with WM2XAN in Michigan on 40.662 MHz. (Note: Local time in the USA would have been late on the evening of the 8th)

The distance was around 1,230 kms and it's possible that the propagation mode was mid-Winter Sporadic-E. WM2XAN reports that it may have been due to Auroral-E. The K-index was at 5 late on the 8th of January which gives some credence to the Au-E theory.

While some of the US experimental stations have exchanged WSPR reports up to now, this is I think the first actual contact between two US experimental stations on the 40 MHz band.

The PSKReporter website shows that WM2XEJ was also heard locally by KS4OT in Georgia.

Once we get to late April and early May and the start of the Sporadic-E season, 40 MHz contacts and reports like this should become more common.

Link...
1) For more information on the 40 MHz band, see my page... https://ei7gl.blogspot.com/p/40-mhz.html

Successful WSPR reports on the 40 MHz band in the USA - Nov 2021

Over the last few months seven stations in the USA have received experimental permits for the 40 MHz band... see previous post.

While a few have tried FT8, a number have been using the WSPR mode as an experimental beacon. 

A list of of some of the reports are shown below with maps shown above.

1) WX2XCC in California is operated by Chris, N3IZN and he has a remote receiver listening for his own WSPR transmissions. During what was probably a Sporadic-E opening on the 40 MHz band, he was decoded by VA7MM in Vancouver in western Canada at a distance of 1819 kms.

UTC (y-m-d) TX txGrid RX rxGrid MHz W SNR drift km
2021-10-28  22:12 WM2XCC DM13 N3IZN/SDR DM13ji 40.663484 2 7 0 21
2021-11-28 17:48 WM2XCC DM13 VA7MM CN89og 40.663488 2 -17 0 1819

2) WM2XEJ in Georgia is operated by Tom, WB4JWM and his WSPR signal has been reported by two stations... NZ2X and N4WLO.

UTC (y-m-d) TX txGrid RX rxGrid MHz W SNR drift km
2021-11-23 15:08 WM2XEJ EM83 NZ2X EM83ij 40.663473 10 5 0 25
2021-11-29 17:48 WM2XEJ EM83 N4WLO EM50uo 40.663433 10 -23 0 589

While NZ2X is a local station, the distance to N4WLO is 589 kms which is pretty short if it was Sporadic-E.

3) WX2XCW is operated by Hal, NR7V is just in the far north-west of Washington state. He is very close to the city of Vancouver and all of the reports are from local Canadian stations.

UTC (y-m-d) TX txGrid RX rxGrid MHz W SNR drift
2021-10-28 22:06 WM2XCW CN88 VA7MM CN89og 40.663527 0.2 2 0
2021-10-28 22:06 WM2XCW CN88 VE7UTS CN89li 40.663524 0.2 -8 0
2021-11-22 18:16 WM2XCW CN88 VE7RPX CN89lh 40.663529 2 -16 0
2021-11-22 18:36 WM2XCW CN88 VE7AFZ CN89ji 40.663527 2 -28 0

Overall, it's still early days but hopefully more stations will start transmitting on WSPR and more will start listening and uploading their spots to the WSPRnet website.

Link...

1) More info on my 40 MHz page

There are now 7 experimental US stations on the 40 MHz band - Nov 2021

18th Nov 2021: In previous posts, I detailed how some amateur radio stations in the USA had managed to obtain special experimental permits to operate on the new 40 MHz band. 

The first 40 MHz permit WL2XUP near Atlanta was issued back in June of 2021. See this previous post.

The second permit WL2XZQ near Houston was issued in August. See this previous post.

As of mid November 2021, there are now seven experimental permits for the 40 MHz and these are shown on the map above and in the list below. An eight from Alabama is pending.

The permit allows for experiments in the frequency range of 40.660 to 40.700 MHz which is the 40 MHz ISM band (Industrial, Scientific, Medical).

The permits allow ERP powers in the region of 100-400 watts and the license lasts for two years.

Propagation: If you examine the map above, you'll note that the distances between the various experimenters.

For example, take WM2XCS in New Jersey. He is 950kms from WM2XAN, 1200kms from WL2XUP and 2250kms from WL2XZQ. 

WL2XZQ in Houston is 1800kms from WM2XAN.

WM2XCC in California is 2100kms from WL2XZQ, 3050kms from the stations near Atlanta, 1800kms from WM2XCW.

WM2XCW is the far north-west of Washington state is 3150kms from Houston and 3900kms from New Jersey.

It is highly unlikely that tropospheric propagation will contribute much to the experiments. The distances for aircraft scatter are also likely to be too far. Some in the 500-1200km range may manage to complete contacts with digital modes like MSK144 with meteor scatter.

The real workhorse on the 40 MHz band is going to be Sporadic-E. There may be a few openings over the next few months but things will really get going at the end of April 2022. At that stage, the experimental stations will have had time to get their radios and antennas ready for the band and I'd expect that contacts in the range of 800 to about 2200 kms will be common with something in the region of 1700kms being the most common distance.

In the second half of May 2022, double hop Sporadic-E openings will become more common and at that stage, contacts from the west coast to the eastern half of the USA should be possible.

Crossband: Just like in Europe, there are likely to be crossband contacts from 40 MHz to 28 MHz and from 40 MHz to 50 MHz with those who cannot transmit on the 8m band. 

Someone doesn't need an special 40 MHz permit to take part in the experiments. The experimental stations are likely to be using SSB, CW, FT8 and WSPR and I'm sure they would like to make as many crossband contacts as possible as well as receiving any reports of their transmissions.

Analysis: It's great to to this surge in interest in the 40 MHz band in the USA. The 8m band is NOT just another band. It is halfway between the 28 MHz and 50 MHz bands and it can be useful for exploring just how high the maximum usable frequency (MUF) goes as the solar activity increases as we head towards the sunspot maximum.

For example, it would be interesting to know what kind of solar flux/sunspot number is required before there are east-west openings between say California and the eastern part of the United States.

It would be really nice if some stations in South America were able to listen on the 40 MHz band and then try to complete some crossband TEP contacts with experimental stations in the southern states of the USA.

Links...
Check out my 40 MHz page for more info... https://ei7gl.blogspot.com/p/40-mhz.html

Radio amateurs in the USA to lose the 3.4 GHz microwave band

 

In a ruling issued on the 2nd of October 2020, the Federal Communications Commission (FCC) in the USA announced that the amateur radio service is going to lose access to the 3.4 GHz microwave band. It is proposed that the spectrum from 3.3 to 3.55 GHz be cleared for 5G networks.

Up to now, radio amateurs in the US had a secondary allocation from 3.3 to 3.5 GHz based on a non-interference basis to primary users. The FCC have now proposed clearing 3.4 to 3.5 GHz in the short term and 3.3 to 3.4 GHz at a later date.

Excerpt from the ruling regarding the amateur allocation...

FCC petitioned to open up 45 to 50 MHz for DRM+ broadcasts in the USA

Currently most of the terrestrial radio stations in the USA broadcast either on the AM band from 540 to 1700 kHz or on the FM band from 88 to 108 MHz. At the end of September 2018, the FCC announced that there were 4,464 stations on AM and 10,867 stations on FM [1].

Due the crowded nature of the existing bands, it has been hard to introduce new digital radio formats.

DRM or Digital Radio Mondiale is a digital format designed to replace existing AM transmissions with clearer audio and with just 20% of the power. DRM+ is the format for VHF.

WRNJ Radio co-owner Larry Tighe has now filed a petition for rulemaking with the FCC, asking that the 45 MHz to 50 MHz band on the VHF spectrum be reallocated for DRM+ transmissions.

In a statement, Tighe said... “The 45–50 MHz band was allocated to two-way radio users in business and government, who have since migrated to higher bandwidths where they can use handsets with smaller antennas. As a result, this spectrum is extremely quiet right now. WRNJ monitored this bandwidth for an extended period of time, and heard very few distant signals.”

“There were 660 TV stations between Channels 2 and 7 before the transition to UHF for HDTV. There are now only approximately 60 TV stations in the USA on those old VHF channels. There is plenty of spectrum to share with a new service, i.e., DRM+ or any modulation, if the FCC really wanted to move AMs.”

Even though the DRM standard has been around for over a decade, it is only recently that it has begun to make serious inroads to the broadcasting scene with India, China and Russia showing an interest. One of the current problems is the high cost of DRM receivers which is prohibitive to consumers in developing countries.

Obviously if the USA opted for a new DRM+ allocation, it would give the format a huge boost. If it turned out to be the 45 to 50 MHz allocation then it raises the possibility of long distance reception by means of Sporadic-E during the summer months or via F2 propagation around the peak of the sunspot cycle.

More info in the links below.

Links...
1) FCC stats for the number of AM and FM stations at the end of Sept 2018
2) https://www.radioworld.com/tech-and-gear/u-s-based-shortwave-broadcasters-eye-digital
3) Previous post - Russia proposes to use DRM on 65.9-74.0 MHz