Upgrade to the Irish 70 MHz beacon EI4RF - Apr 2021

The Irish 4m beacon EI4RF has now been upgraded and is now transmitting on 70.013 MHz. It was previously operating on 70.130 MHz due to the limits of the older Irish 4m band. 

It is still located to the south of Dublin in the locator square IO63VE.

It is running 25-watts into a 3-element Yagi pointing east (90 degrees). The map above shows the beam heading with the -3dB (half power) headings as well.

EI4RF: 3-element Yagi for 70 MHz

The signal for the beacon comes from a GPS locked RFzero board and it uses the following format per minute: 3 x 15 second FT8 transmission and 1 x CW transmission.

Analysis: This new upgraded EI4RF beacon should prove to be a valuable propagation tool for the 70 MHz (4m) band especially as it is running 25-watts into a directional antenna with about 6dB (x4 time power) of gain. 

Anyone in England up to a distance of 500kms with a very modest station on 4m should be easily able to hear the beacon via tropo. Under enhanced tropo conditions, well equipped stations in the Netherlands at about 700-800kms might hear it.

As regards Sporadic-E, it should be very strong in the range of 1500 to 2200kms when the band is open... e.g. Poland, Baltic states, Croatia & Slovenia. During stronger openings when the MUF is higher, shorter distances down to 1000 kms may be possible... e.g. Germany.

Reception outside the -3dB points will be possible but obviously the further away from -3dB points you get, the weaker the signal.

EI4RF Site Profile: I have done up a site profile for the EI4RF site and it is shown below with the outline of the horizon.

I have included the 0 degree and 1 degree lines and I have coloured in the sea in light Blue to make it clearer.

As you can see, the beacon is on an elevated site and is looking down at the Irish Sea. Some of the mountains in the NW of Wales (90 deg) at a distance of 150kms or so are also visible. The plot clearly shows that there are no local obstructions between the -3dB points which is very good.

Outside of the main beam heading to the East, the path to the rest of Ireland is largely blocked by local hills and mountains. In the direction of Waterford (210 deg), the horizon has an elevation of about 3 degrees. In the direction of Cork (227 deg), the horizon rises to about 5 degrees. To the west, the horizon is over 7 degrees. It's highly unlikely that this beacon would be heard across the North Atlantic if there was ever some double hop Sporadic-E.

In conclusion: This beacon with its 25 watts should be easily heard in England via tropo and in eastern Europe via Sporadic-E. The inclusion of the FT8 digital mode is a welcome touch as it allows people to hear signals buried in the noise and there is already a lot of people using that mode. Any reception reports can be automatically uploaded to the PSK Reporter website to alert others of any opening.

Thanks to Tony, EI7BMB and Tim, EI4GNB who got this upgraded 4m beacon up and running.

* * * 

Other site developments: From Tim, EI4GNB...

EI0SIX had a mild tune-up, as one of the pair of antennas had gone a bit droopy, now the SWR and bandwidth are excellent. It remains 40w to a pair of loops phased.

EI1KNH on 8m has had it's monopole antenna moved to the top of the 4m mast, away from the FDP for 5m, and now has a much healthier looking lot on my VNA. No more interaction with 5m. It's happy on 40w from the NXP PA.

EI1KNH on 5m now runs FT8 for 3 periods of 15 seconds, then runs a slow CW ID and a long carrier - previously it had been looping FT8 every 15 seconds. It's PSU was toast, and was causing hash all over HF to the remote stn there, so it's temp on the same PSU as EI0SIX. No change to the chain, 25w to a folded dipole.

70 MHz permits in Iceland allowed for 2021 & 2022

 

The Icelandic Radio Amateur federation (ÍRA) has been notified by the countries Post and Telecom Administration (PSF) that permits to operate on the 70 MHz / 4-metre band will be allowed from another two years. 

The frequency range is 70.000-70.250 MHz and is valid for two years from the 1st of Jan 2021 to the 31st of Dec 2022.

As before, the following conditions apply:

(1) Maximum bandwidth is 16 kHz. No molding conditions; 

(2) the maximum radiated power is 100W; 

(3) the authorization is subject to the interruption of other electronic communications activities, transmissions must be stopped immediately and 

(4) call signs must be used at the beginning and end of the electronic communications connection and at appropriate regular intervals during the electronic communications connection.

Licensees must apply for authorization to the PTA before transmissions begins in the frequency range. 

The map above shows the distances in kms from Reykjavik, the capital of Iceland. 

Analysis... It's very likely that stations on 70 MHz from Iceland will be heard elsewhere in Europe from May to July during the Sporadic-E season. These will likely be in the range of 1000 to 2300 kms with most in the range of about 1300 to 2100 kms.

As the map shows above, the countries within one-hop range are likely to be the UK & Ireland, Belgium, Netherlands, NW Germany, Denmark, Norway & Sweden.

Distances greater than 2300kms may be possible be some form of multi-hop propagation but this is rarer at 70 MHz as compared to 50 MHz where it is a lot more common.

Temporary 70 MHz permit for SM0TSC in Sweden

 

While the 70 MHz (4m) amateur band is allocated across much of Europe, it is allocated to 'Land Mobile and Fixed radio' in Sweden. The Swedish licensing authority however do allocate temporary 4m permits to radio amateurs.

On the 26th of January 2021, Johan SM0TSC got a temporary 6-month license for the 70MHz band. The terms of the permit are that he must operate on the spot frequency of 70.1375 MHz and the ERP (Effective Radiated Power) of his transmissions must be 25 watts or less.

SM0TSC is near the capital Stockholm and his locator square is JO99CF. In recent months, both SM4KYN (JO69XH) and SM7CAD (JO77UM) have been active on the 70 MHz band with temporary permits.

The map above shows the location of SM0TSC. The major activity on 70 MHz will be in early May when the summer Sporadic-E season starts. The typical range for Sporadic-E on 4m is about 1000 to 2300 kms with the majority in the 1200 to 2000 km range.

There is also license free radio band in Sweden at 69 MHz and these FM signals were often audible here in Ireland during the summer of 2020. It's likely that the Swedish radio amateurs on 70.1375 MHz should be easy to work from the UK and Ireland as well.

Credits: Thanks to Rob PE9PE for the original news item

D4VHF on Cape Verde plans to be on the 70 MHz band during the Summer of 2021

The D4VHF team on Cape Verde Islands have just announced that they plan to be operational on the 70 MHz (4-metre) band during the Summer of 2021!

They will be using a 4-element Yagi (shown above) beaming towards Europe with an output power of 500-watts.

As the map shows below, the Cape Verde Islands are a long way from Europe and some multi-hop propagation will likely be required.

Analysis... The annual Sporadic-E season in the northern hemisphere normally starts in late April and runs until mid-August. 

It's likely that the first Sp-E openings from Cape Verde will be single hop with a maximum range of 2300kms or so. Stations in the Canary Islands (EA8) at 1500kms or so are ideally placed for a one-hop Sporadic-E opening on 70 MHz.

To get further up and into Europe, it will likely require a double hop opening with ranges of say 2500 to 4400 kms. This should allow stations in the UK and Ireland to work Cape Verde on 4m.

Obviously the more hops that are required for a path to open then there are statistically fewer openings. However, 70 MHz isn't that high a frequency when it comes to Sporadic-E and there should be occasions when even three hops or even four hops are possible. I suspect though that multi-hop openings like this to say central or northern Europe may only occur once per season? We'll see.

Tropo Ducting at 70 MHz???... The D4VHF station on Cape Verde has made many spectacular contacts on 144 MHz and 432 MHz thanks to a marine duct off the north-west coast of Africa.

This marine duct establishes itself for long periods at different times of the year and this allows stations on the coast of Spain and Portugal to work D4VHF on 2m with relative ease over a 3000km or so path. At times, this duct moves further north allowing stations in the UK and Ireland to get in on the action.

This duct behaves like a waveguide and it has certain dimensions. As such, like a waveguide it will have a lower cut off frequency below which signals will not propagate.

The big question is if 70 MHz signals with a wavelength of four metres will be able to propagate through this marine duct?

Will the 70 MHz signals from D4VHF be able to reach the Canary Islands (~1500kms) by tropo ducting? The south-west coast of Spain and Portugal at 2800kms? Will the frequency be too low?

If the marine duct does propagate 70 MHz signals then there is the possibility of it coupling to Sporadic-E openings more often. If not then it looks as if rarer double hop Sp-E might be the only option.

In conclusion... I'm sure many fans of the 70 MHz band will look forward to D4VHF from Cape Verde appearing on the band during the summer of 2021. Single hop and even double hop Sporadic-E contacts I believe are a forgone conclusion and these shouldn't be that difficult.

What I find most interesting however is the ability of a 70 MHz signal to propagate inside a marine duct. Is it possible? If it does happen, is it common? And how far?

It'll be interesting to see the results.

Australian authorities turn down request for 70 MHz allocation

There was a news item on the Internet recently about how the Australian regulator was not considering an allocation at 70 MHz for radio amateurs.

“We note the continued interest in this band from the amateur community. The ACMA will not be further investigating this matter at this time.

The ACMA considers that operating amateur services in this frequency range is not feasible as it would be inconsistent with ITU Radio Regulations and existing services are already operating in the frequency range. 

This frequency range is used by a variety of fixed and land mobile services as supported under the VHF mid band (70–87.5 MHz). Class licensed devices authorised under the LIPD Class Licence operate in the frequency range 70–70.24375 MHz.”

This was the reply to a submission to an earlier submission by the Wireless Institute of Australia (WIA) to the ACMA which essentially consisted of a single sentence... "10. The WIA still has an interest in an allocation at 70 MHz."

ITU Region 3... As can be seen from the map below, Australia is in ITU Region 3 while nearly all of the 70 MHz allocations are in Region 1 countries.

It's a pity that something like a 4m beacon couldn't be established in Australia or even a or a few experimental licences for the band.

It would be interesting to see if say someone in Perth on the west coast (VK6) could investigate if there is a multi-hop Sporadic-E path across the Indian Ocean to South Africa or up to the Middle East.

What would be good is for one of the smaller countries in Region 3 to give a small allocation for the 4m band which would then set a precedent. Even a 200 kHz wide segment of spectrum dedicated to weak signal modes would satisfy most requirements.

6000 km plus contact made between the Canary Islands & Kazakhstan on 70 MHz - 18th June 2019

I recently came across details of a remarkable 70 MHz contact that was made on the 18th of June 2019 between EA8DBM in the Canary Islands and UN7MBH in Kazakhstan. It's possible that someone hadn't noticed the date on the FT8 screen capture when posted online and thought it was from 2020 instead.

Despite the fact that it's over a year old, it was still an interesting contact as it was in the region of 6,112 kms. As you can see from the screenshot below, the contact was made via the FT8 digital mode.

While most Sporadic-E contacts on 70 MHz might be in the region of say 1500 to 2200 kms, the 6000 km plus distance for this contact suggests that it may have been triple hop Sporadic-E.

Triple hop Sporadic-E on 50 MHz is interesting but not that unusual. After all, most of the 6-metre contacts between Europe and the USA are triple hop or more.

However as the frequency get higher, a higher level of ionisation is required. At 70 MHz, single hop Sporadic-E is very common, double hop is a more unusual but triple hop is more exceptional.

I searched on the net for more information on this remarkable contact but there didn't seem to be anything about it. I thought I'd make a post about it so that at least a record of it now exists.

I know that there have been triple hop contacts from the north-west of Europe to the Arabian Peninsula but I don't think any of those exceed 6000 kms.

Falkland Islands gain access to 70 MHz band

Dave, EI3IO, reports that the Falkland Islands Telecoms Regulatory Body has granted access for radio amateurs to the 4-metre band from 70.000 MHz to 70.500 MHz using a maximum power of 1 kW on a secondary basis since 15 November 2019.

The Falkland Islands (VP8) is now one of the few countries in the southern hemisphere with access to this unique VHF band. The map below shows the countries that have some form of access to the 4-metre band.

Red & Blue = Countries with some form of access on 70 MHz

What is perhaps unique about the 70 MHz allocation in the Falkland Islands is the sheer isolation of the location. There are no countries within a normal one-hop Sporadic-E range of the islands and indeed, the closest other radio amateurs on 70 MHz are probably in South Africa, a distance of some 6,200 kms!

This raises the very real possibility that contacts outside of the Falkland Islands may not be possible on the band.

The most likely possibility if at all would be a multi-hop Sporadic-E link across to South Africa but it would probably require 3 hops at 70 MHz which isn't easy. The other possibility is St.Helena in the South Atlantic but this is almost as far.

There may be a remote possibility of Sporadic-E link to some Trans-Equatorial Propagation (TEP) to the north but this seems unlikely.

Link...
1) https://www.regulatorfi.org.fk/spectrum/national-frequency-allocation-table/60-fi-spectrum-allocation-table-v2-0-full-table-public-pdf/file

Germany to get 70 MHz allocation from 2nd May to 31st Aug 2018

I saw a news item recently that Germany is to get a temporary allocation on 70MHz again in 2018 from the 2nd of May to the 31st of August.

The allocation will be from 70.150 - 70.180 MHz. This does of course coincide with the Summer Sporadic-E season which will greatly increase the chance of making some contacts.

The suggested range for someone in central Germany is shown below....

The shortest skip distance is likely to be around the 1000 km mark and will probably require a very intense opening, possibly from mid May to early July.

The longest skip distance should be around the 2200 km mark. It's likely that the most common openings will be around the 1500 to 2000 km range.

If you live in Ireland, it might be handy to check for some useful markers. If you can hear Polish radio stations on 88-108 MHz, then check 70MHz to see if it is open to Germany. If you can hear Dutch or Belgian stations on 50 MHz, then check 70 MHz.

Proposed changes to the 70 MHz Band in Ireland

This is the current IARU Region 1 band plan for 70 MHz band...

The Irish allocation is from 70.125 to 70.450 MHz while the British one is from 70.0 to 70.5 MHz.

What it has meant is that the UK calling frequency of 70.450 MHz is actually on the limit of the Irish band. If any EI station were to transmit there on FM then their side bands would be outside the Irish allocation.

The most recent newsletter from the Irish Radio Transmitters Society carried details on submissions that had been made to Comreg, the Irish licensing authority. While many of the submissions were declined, it was obvious that Comreg was using European Common Allocations as their guide. i.e. if the European agreements said something about the amateur radio service then that's what they were likely to implement.

As regards to the 70 MHz / 4 metre band, they are guided by footnote ECA9 in the CEPT European Table of Frequency Allocations.

This is what the International Amateur Radio Union (IARU) said about ECA9 / EU9...

The 70MHz band is increasingly recognised as being appropriate for amateur allocations. In the CEPT area this progress is now recognised in the European Table of Frequency Allocations by Footnote EU9 which states:
EU9: CEPT administrations may authorise all or parts of the band 69.9-70.5 MHz to the amateur
service on a secondary basis. In addition it is worth noting that there is some experimental access on a national basis in the range 69.90 - 70.0MHz in cases where 70MHz is not available.

In response to the IRTS proposal, Comreg said the following about 70 MHz...

"Comreg's work plan for radio amateur services is to make available the following bands:
. the 30-49 MHz and the 54 - 69.9 MHz and 69.9 - 70.125 bands to facilitate propagation beacons, digital amateur television repeaters and to align current allocations with those in the European Common Allocation Table: and 
. the 70.45 - 7-.50 MHz band to align it with the European Common Allocation Table.

So it looks as if they will be extending the Irish allocation so that it will cover 69.900 to 70.500 MHz. This is likely to be implemented soon...perhaps early 2017???

This is how the new Irish allocation will look now compared to other countries...

As can be seen, Irish stations will now be able to work other countries simplex without having to resort to split frequency operation.

Overall, a very positive result!

Additional info : 
1) Region 1 Band Plan... http://www.irts.ie/dnloads/IARU-R1-Bandplan-VHF-UHF.pdf
2) 70 MHz website... http://www.70mhz.org
3) Comreg document 16/19 (See Page 69)... https://www.comreg.ie//csv/downloads/ComReg_1649.pdf
4) CEPT European Allocation Table... http://www.erodocdb.dk/Docs/doc98/official/pdf/ercrep025.pdf