8m (40 MHz) Band

This is midway between 10m and 6m.  It should be a future amateur allocation. It is already available in a very few countries and there are some experimental licences in some administrations.   

In my view there is an overwhelming case for a tiny 5 kHz amateur band at 40.680-40.685 MHz. This should be strictly no  speech, narrow digital modes only and allocated to real experimenters by NoV or equivalent. The allocation should probably be secondary, and strictly non-interference. Just think of the real benefit to propagation research and self training.

Try to encourage your administration to give some access.

My own NoV application was sent to  OFCOM and the RSGB on October 5th 2021.  The NoV was rejected (totally stupid!), so I had to apply for a Trials and Innovation licence (£50 for 12 months!!) that was approved. This allows me to use digital modes from 40-42MHz for 12 months from April 2nd 2022 at 5W.   Others have also been approved. The form is on the OFCOM website.  With this licence I do not need a callsign and I cannot be traced!! How stupid is that! Bizarre.  In my view OFCOM, the FCC and the RSGB have behaved appallingly.  Certainly in the UK there is a shortage of RF engineers and self training should be encouraged. Surely a tiny 8m narrow digital only band would help?

Mostly I am on FT8 just above 40.680 MHz in a way that does not interfere with others.  Other modes may be tried for specific skeds.

UPDATE  June 1st 2023:   My T&I licence has been extended to April 2024.

My Gear

For 8m, I use my FT817ND. This was widebanded by the dealer when I bought it. I tune down to 8m from the 6m band. I tried tuning up from 10m, but TX stopped at 33 MHz. Ideally, I should put  40.680 MHz DIG in one of the memories. I have yet to do this. The FT817ND produces 2.5W.  My antenna is just a low wire dipole (see photo).

Results

So far,  I have been spotted in 21countries and 4 continents on 8m QRP FT8 TX including 2 in the USA all with just 2.5W and a low wire dipole!   Most of these were via Es (some probably F2)  propagation.   On RX, I have spotted a couple of stations in South Africa.  As I keep saying, this should be a tiny amateur band! 

I have written to the RSGB General Manager with a request he forwards it to the VHF Manager.   To say the response was pathetic is an under-statement.

Conclusions

Overall, 8m is a really interesting part of the spectrum. It needs a small amateur radio allocation across the world to really encourage research and self training.

It most definitely would not be "more of the same" as some at OFCOM seem to think. In my view a really narrow amateur allocation without speech would prevent this.

Without any commercial amateur transceivers available for 8m, it is very unlikely anyone apart from serious experimenters would be interested.

8m ISM Local WSPR Testing                                            


Introduction


Recent emails with OFCOM convinced me that anyone in the UK may legally transmit with beacons in the 8m ISM band without a licence as long as they comply with the technical requirements and the interface requirements shown in IR 2030.  At 8m, this means 10mW ERP maximum 40.66-40.70 MHz, which at first sight, doesn't look much. Tests were carried out locally to find out how effective this low ERP might be. A modified FT817ND was used plus a 20dB attenuator (using standard values - there are lots of calculators on the internet) right on the output to avoid any cable radiation. My antenna is a low 8m wire dipole.  Not being a legal expert, it is up to other people to convince themselves of legality.


Tests


Initially the modified FT817ND was used with a 40.680 MHz low wire dipole at 1W with WSPR with the call G3XBM and reports gathered. Under the terms of my 8m T&I permit, this is perfectly legal.  Next day, a 20dB attenuator was added right on the output of the FT817ND and transmissions with just 10mW ERP were carried out using the callsign 8M3ISM.  Callsigns are not legally needed for ISM beacons.


Results


Fewer local stations spotted me at 10mW ERP, but 2 stations at about 17km plus one closer did decode me. As far as I know, not a single station used a 40 MHz antenna!  Bernie G4HJW spotted my 10mW 8m WSPR despite using a 6m vertical antenna when my 8m dipole was horizontal!  He is about 10km from me.



Conclusions


10mW ERP WSPR at 8m could be useful. With proper 8m antennas, better results are probable. With good Es propagation Europeans could copy this. Without the need for a licence in the UK many more people could access the 8m ISM band for beacons perfectly legally. 



Acknowledgements


Cambridge and District Amateur Radio Club (CDARC) members and other locals who, with my permission, took part in these tests helped a great deal.  Without this help, these tests would not have been possible.



References


OFCOM  https://www.ofcom.org.uk/home 

IR 2030   https://www.ofcom.org.uk/__data/assets/pdf_file/0028/84970/ir-2030.pdf

Email dated Nov 30th 2022 sent to the RSGB:


"Dear Sir/Madam

Please would you clarify the position of the RSGB on a possible amateur band at 8m?  


It would appear both the RSGB and OFCOM are against this. Instead, true experimenters (like me) keen on self training have had to apply for, and pay £50 annually, to be able to do this.


As a retired senior manager in the communications industry, I am only too aware of the shortage in the UK of decent RF engineers, so I would have expected both the RSGB and OFCOM to support this.


The oft used phrase is "not more of the same".


These are my proposals:

If the RSGB actively supported this, it would certainly advance radio science and self training, in a way that discussing allotments on 80m with commercial gear cannot. Not only that, OFCOM has released 2000 kHz of VHF spectrum for amateur DATV experiments, which is great. This 8m band would be just 5 kHz wide for serious research and self training, which is what our hobby is surely about. 


With no commercial gear available except by modification and with no speech, only true experimenters are likely to apply for 8m NoVs.


With 2.5W and a low wire dipole I have reached 3 continents and 16 countries on 8m FT8 with my 8m T&I permit. It would be good to have a tiny amateur band at 8m to advance self training and radio science.


Your response is eagerly awaited. This would most definitely NOT be "more of the same". 8m is at the very boundary where HF meets VHF and is therefore ripe for research.


73s

Roger Lapthorn G3XBM"