I'd imagine that the first half of the subject line would have had a few hearts in a few throats so I thought I'd clarify before people clicked on the link.

I've just read on the British forums that the BBC is going to close down a couple of dozen AM (MW) radio transmitters where the service is simulcast on digital radio. It's a move that would clearly work better there than here, given that there are instances where listeners do not have access to a digital radio in order for AM to be superseded.

To date, only the capital cities in Australia host digital transmissions (that I know of) and most new cars are still not fitted with radios that receive DAB+ transmissions. Some that do are a few Hyundai and Toyota models and the ZB Commodore is also expected to have such a radio fitted. The problem with cars, however, is that DAB+ cannot be received in motorway tunnels (only Sydney's tunnels have been tested), so the signal drops out once you enter the tunnel portal. Mobile phone and analogue radio transmissions are repeated and the tunnel operators can over-ride radio transmissions with safety messages, regardless of what station you are on.

With digital radios to be fitted to a wider ranger of cars over the next few years it'd be worthwhile for tunnel operators to consider adding DAB+ to their rebroadcast operation, with tunnel safety in mind, at least.

For the Brits though, digital radio is definitely the future - https://vintage-radio.net/forum/showthread.php?t=142432