Apologies for the length of this but needs must! This subject has had a fair discussion on the club nets and I have been receiving direct emails about it so here we go :-
By now you should have received “that” email from OFCOM detailing new conditions to your amateur radio licence. If you have not received one yet check your spam folder and also ensure that your details are up to date with OFCOM (you should be doing this at least every 5 years to keep your licence valid anyway)
These new conditions are applicable to us all, regardless of licence level, as even a QRP station running a beam can easily have an output above the minimum 10W EIRP they specify!
These changes have caused much bleating , discussion and confusion on various forums and social media sites, many saying it will be the death of amateur radio as we know it, it’s methodology is wrong or that it is “all too difficult”. Many of the posts are from well educated folks and they are trying to read far to much into it!
Regardless of all the fuss or our personal views, it is now a requirement that we have to comply with, or accept the risk of enforcement action by the regulator which could include licence revocation.
These measures are intended to prevent members of the public from any excessive EMF our stations may generate, in other words to keep a safe separation between the public and our antennas (which most of us already do).
The OFCOM email contains a link to their calculator tool which is a rather blunt instrument, The RSGB have worked with OFCOM to produce a calculator that is far more suitable for our needs, and its results will satisfy OFCOM’s requirements.
The calculator is available to all on the RSGB website along with guidance and background information, you do not need to be a member to access it.
If due to your antennas location you are unable to meet the separation distances required all is not lost, the OFCOM EMF guidance document explores possible control measures we could take.
We have been given the following time periods to make sure we have up-to-date records in place:
a) Until 18 November 2021 for any equipment which operates on frequencies at or above 110 MHz. b) Until 18 May 2022 for any equipment which operates on frequencies above 10 MHz but below 110 MHz.
c) Until 18 November 2022 for any equipment which operates on frequencies at or below 10Mhz.
Currently (and this explains the long lead time) the calculators are no good for frequencies below 10Mhz, work is ongoing to resolve this, and the RSGB are working to produce Pre Assessed Configurations for antennas working the lower bands, there is an example on the RSGB site, it is worth reading and it shows how small an exclusion zone can be for a 40/80m 1⁄2 wave dipole.
At this time there is no need to panic, don’t try to read too much into it, sure you can get all scientific and model your antennas with the likes of MMANA-Gal or other tools, but the results will be very similar in most cases. Keep things simple, have a read of the website and have a play with the calculator.
The calculator is easy to use, download and run it, it may open in “read only” if so you will have to allow editing, then simply enter your details and see the results. There is a tutorial video on the website if you need it.
When doing your calculations for each antenna/frequency/power combination I suggest a “worst case” approach, that is, run the calculator on the highest power and Voice FM transmit mode. If you are good on FM you will be ok on other modes.
Print off the results for each Band/Power/Antenna along with any control measures you may need and file away somewhere safe. Should you ever get a knock on the door from OFCOM about EMF issues these documents will be what they are looking for.
If after reading this you are still unsure, or need help with printing or anything else please feel free to ask and one or more of the club members will help you.
73, Kevin (M0KKM)