Originally Posted by Hybrid tellies:
“I am not sure if they can carry a secondary service on the local commercial mux. Also Local DAB has a very limited coverage compared to either AM or FM.”
It's completely within the specs - just needs the will to put it in there - IIRC one of the Scottish Local multiplexes had three services as secondary channels to one another for quite a while - can't remember the exact multiplex so I'll use Clyde 1 and 2 as a placeholder, 3C was part of it though:-
Clyde 1, with Clyde 2 and 3C as secondaries
Clyde 2, with Clyde 1 and 3C as secondaries
3C with Clyde 1, and Clyde 2 as secondaries
The coverage issues with the local multiplexes should be addressed as part of the build out plan over the next few years. (It's kinda annoying the UK haven't made more use of these dynamic opt-outs - Five Live on some Saturdays would benefit gratley from them as would many BBC LR stations* - satellite TV is also a big example of wasted capacity going (see BBC ONE and it's two dozen simulcasts - many of those could be rained in if we took some lessons from the Germans perhaps offering more part-time red button)).
Also not every local multiplex has less coverage than the analogue stations - IIRC BBC Nottingham is one of the stations which has better coverage on DAB than FM (and certainly better than MW) - the only extra planned transmitter seems to be a filler for when expansion of other multiplexes increases incoming interference.
* Heck I'd even go as far as to suggest that once the local radio build out is complete the BBC World Service should be transferred to the local multiplexes allowing BBC LR stations to run with 3x64kbps opt-outs if needed - e.g. Mansfield Town, Nottingham Forest, and Notts County and for the once in a blue moon when a fourth opt-out is needed they could even take the World Service off-air for a couple of hours.