One confidential respondent suggested that a review of the AM planning standard is overdue, as man-made electrical noise has now replaced night-time sky wave interference as the dominant interference to AM radio reception.
That was what Lawrie Hallett suggested in his Radio Caroline looks to the future article on RedTech last October. "Currently considered to be 66dBuV (2mV per meter), a move to, say, 72dBuV would provide a clear engineering rationale for further increases in transmitted power levels."
Ofcom response: Given the limited number of services remaining using AM transmission, and the trends in listening, we deem it would not be efficient use of our resources to review the AM planning standards.
As to increasing power the previous application already been turned down under the current community radio licence conditions, reasoning given.
https://mb.boardhost.com/FreeRadioForum/msg/1701192310.html
There's been no change to community radio licencing conditions under the Broadcasting Act. The Media Bill changes are for current commercial radio analogue licencees to be able to change their format if they wish to with protection for their local news output requirements.
Norway has turned off most FM transmitters in favour of DAB+, Switzerland is planning to do so in the next few years, Spain is now working towards this following an agreement with one of the telecommunications companies to use their transmitter sites. DAB+, which fades rather than burbles when the signal become weaker thus giving a small increase in coverage area, unlike FM is a single frequency network carrying many stations, and does not suffer from multipath so you are often receiving signals from more than one transmitter without audio distortion.
That's one reason why Norway, Switzerland and Spain, all mountainous countries, are working towards turning FM off. The BBC has said if and when FM is turned off they will add more transmitters to give better national coverage.
As to splatter on SDR's the Stourbridge SDR is 13 miles from Droitwich. The claim of 693 giving interference to Caroline on 648 was first posted several years ago on Digital Spy. There was no splatter then, nor has there been on my occasional checks since. There's adjacent channel interference but none at all on 675 and 711.
http://81.174.134.21:8073/
The Woofferton SDR, which I hadn't noticed before on my occasional visits to the Kiwi SDR website, is 23 miles away.
One of numerous comments on the internet on high power medium wave signals and SDR'S.
Broadcast overload on Kiwi SDR
The Kiwi SDR and Wellbrook loop provide a very good single antenna solution for 0 to 30 MHz shortwave reception. The Kiwi is capable of displaying the complete band of 30 MHz, but the disadvantage is the very high power from some of the LW and MW stations can cause the receiver to overload in the evenings.
https://m0taz.co.uk/2018/09/broadcast-overload-on-kiwi-sdr/
One solution quoted is a notch filter for 909 Brookmans Park. Woofferton could install one for 693. They are also using a Wellbrook Loop as opposed to the 10 metre antenna 3 metres high at Stourbridge thus getting a much stronger signal from Droitwich hence the overload. Advantage is that the Wellbrook Loop will be able to receive long distance signals from North and South America, Asia etc during favourable propagation conditions.
Same splatter from strong signals on mediumwave when near the transmitter occurs on domestic and car radios.
Previous Message
That was my interpretation too, that both bandwidth and power are up for negotiation and if you dont ask you dont get. That said the effect of widening the bandwidth will be lost on many modern AM receivers with a fixed 9khz channel spacing and a brick wall IF filter. An older analogue tuner would be great as you can use the old 'tune off to one side' trick to get the extra few khz of audio. Further to that, my hearing peters out at about 10k anyway so Im not missing much Previous Message
Read on a bit Tom, & your get QUOTE:
"If any existing AM licensee wishes to increase transmission power,
they can make a proposal for a licence variation. Ofcom would consider such requests taking
into account matters such as interference to other services, the UK’s international
agreements and the circumstances of the original licence award." Unquote.
Yes there is a lot about wider bandwidth - it seems widening it to 9khtz, is the only worthwhile change, & that would depend on adjacent channels that are in use.
Reading between the lines - OFCOM are seeing a big loss of income from the "Big boys" no longer using MW - so they "have to be seen" to make MW attractive to any new users, otherwise it will look like OFCOM - who have a duty to make good use of the whole spectrum (EG sell as many licences as they can, within technical constraints)
I'm sure Caroline would not mind one little bit, in being a guinea pig in this aim, with 9khtz & 10kw.
OFCOM really have no excuse now the Big Boys have abandoned MW. Their big mistake in my opinion, as overall, MW goes much further with just one TX, for a given power, than FM or DAB ever will.
Those systems are OK in big towns & Cities, but are pretty useless in Hilly & woodland areas - I speak from personal experience, living in Thetford forest ! - OK AM does not have the high quality, but at least MW is mostly a solid signal & does not go silent or start Gurgling - as DAB is very good at ! Previous Message
I say chaps, aren't we confusing power and bandwidth? Bottom of page 3 of report states:-
" AM radio audio bandwidth
We will adopt the proposals set out in our consultation whereby Ofcom will consider, on a
case-by-case basis, requests from licensees to adopt wider audio bandwidth on their AM
radio transmitters . Such requests will only be granted where technically feasible, and where
they will not cause a significant increase in interference to other spectrum users. "
Message Thread 
Analogue Radio Technical Code - Dave Martin 22/6/2024, 14:16:45
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