Showing posts with label 4m. Show all posts
Showing posts with label 4m. Show all posts

Saturday, December 24, 2022

PJ4MM in the Caribbean gets permit for 40 MHz & 70 MHz - Dec 2022


Martin, PJ4MM on Bonaire in the Caribbean reports that he has just received an experimental license for the 40 MHz (8m) and 70 MHz (4m) band.

These are the frequency allocations with equipment.

8m: 40.680 - 40.700 MHz, all mode, max 50W out, ant modified 4elm 6m yagi (elem length adjusted)

4m: 70.000 - 70.500 MHz, all mode, max 100W out, ant 8elm LFA, fixed to Eu

Martin reports that he has already been heard by FG8OJ on Guadeloupe and K9MU in Wisconsin. 

Rcvr Band Mode Distance Time (UTC)
FG8OJ 8m FT8 865 km 18:16:14
K9MU 8m FT8 4243 km 16:58:44

Martin also reports a signal of -22dB in IM67 in the south of Portugal on 8m but it wasn't reported on the PSK Reporter website.

Martin also says that for 4m, he will be following the Region 1 band plan (Europe) and will be mostly operating on FT8.

Analysis... This is really excellent news as it opens up the possibility of a lot of interesting paths from this southerly location.


On 40 MHz, there will be plenty of openings on F2 up to the USA and Canada and will allow some contacts with the experimental stations there as well as crossband contacts and reception reports. Ironically it may be easier to get reports from the NE of the USA (3500-4000kms) than the SE which may be a bit too close.

There should also be plenty of openings to Europe, especially to Spain and Portugal. It should also open eventually to the UK and Ireland and the question is how far east into Europe will the signal travel.

In the Summer months, there should be plenty of multi-hop Sporadic-E openings from May to July and may act as an early warning for 50 MHz openings to follow.

What I find really interesting are the possible openings on 70 MHz.

Will amateurs in the USA and Canada be interested enough to listen on the band now that there is someone on from the Caribbean on 4m?

Will there be multi-hop Sporadic-E openings on 4m to Europe during the Summer? Almost certainly to Spain and Portugal but further north to the UK and Ireland? How far into Europe? Is it possible to get as far east as Cyprus? Further?


Looking at the southern hemisphere, there are a lot of interesting potential paths.

TEP openings on 40 MHz and 70 MHz to Argentina and the south of Brazil are a given. Will anyone there listen?

From Bonaire to the Falkand Islands (VP8) on 70 MHz?? Is it possible?

Bonaire to South Africa on 40 MHz should be possible on F2 but is it even possible on 70 MHz with multi-hop Sp-E? 11,000kms is a long way on 4m.

And what about the really long paths? From Bonaire to New Zealand (ZL) and Australia (VK) on 40 MHz???

We can be sure that some really interesting paths are going to pop up from this location.

Links for more info...
1) My 40 MHz page
2) My 70 MHz page

Addendum: Martin provides the following information of his permit.
1) 8M license is for 40.66 - 40.7MHz, max 50W, all modes. 
2) 4M license is for 70.0 - 70.5MHz, max 100W, all modes, Antenna restricted direction to Europe. Probably because Venezuela still has multiple analog TV channels in use in this range. 
3) Valid until Christmas 2023.

Thursday, December 22, 2022

70 MHz amateur band released in Switzerland from the Jan 1st, 2023


Some good news! Swiss radio amateurs will gain access to the 70 MHz / 4m band from the 1st of January 2023.

USKA is the IARU member society for radio amateurs in Switzerland and they released the following on the 21st of December.... "4m band released in Switzerland from Jan 1, 2023

After lengthy negotiations with OFCOM, the USKA was able to release the 4m band. The approval is valid from 1 Jan 2023. The following operating conditions apply:

Only radio amateurs with HB9 licenses are allowed to use the band.
Frequency range: 70.0000MHz to 70.0375 and 70.1125 to 70.5000MHz.

Any transmission is prohibited in the range from 70.0375 to 70.1125 MHz.

The maximum power is 25 watts ERP
All common types of modulation are allowed. Use according to the IARU band plan is suggested.
The band is to be used for direct connections. Unattended stations such as relays and Echolink gateways are not allowed.
Remote-controlled stations require a report to OFCOM.
The USKA wishes all 4m enthusiasts every success in exploring the new 4m band.

Bernard Wehrli, HB9ALH - OFCOM liaison officer
"

What to expect???....... See the map below...


Even with an ERP of 25-watts, HB9 stations should have no problem working out to 500kms with weak signal modes.

In the Summer months, Sporadic-E will be the main propagation mode. Stations in the 1000 to 2200 km range should be easy to contact with a peak around the 1500-2000km mark.

Multi-hop Sporadic-E is always possible so there will be more exotic paths.

Source: https://www.uska.ch/4m-band-in-der-schweiz-ab-1-jan-2023-freigegeben/

Thanks to Andrea, HB9DUR for the info source.

Tuesday, April 27, 2021

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.

Wednesday, January 27, 2021

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