Thanks for the clarification! Strange that there should
be no receivers for AM digital:-) In the Old World few radios
are available - and none affordable - which receive DRM,
although DRM test transmissions continue.

The propagation properties of MW and LW (and even SW) signals
would make DRM or similar very attractive - one transmitter
would cover a wide geographical area. In a major emergency, this
would enable communication to the majority from few transmitters.
As it is, we have glorious DAB and DAB+. At 225MHz they are restricted to local coverage and require many relay transmitters and emergency generators to cover the area previously covered by a few AM medium and longwave transmitters. Ideal for North Korea to confound listening to non-Great-Leader broadcasts - and in our latitudes advantageous for
Mad Men advertising philosphers...

'nough said,
Michael