When FM radio was first being introduced, it wasn’t particularly attractive for the AM broadcasters of the day.

For a start, there were very few radio receivers with an FM band, mainly because manufacturers didn’t want to waste money fitting what amounted to a separate front-end for a band which had only a few “experimental” transmissions on it.

Second, AM broadcasters saw FM as a threat, something that might go away if ignored. Or that FM would not attract listeners from AM. Around that time, something happened which made them change their minds: imports of receivers with both AM and FM bands flooded in as the Australian radio manufacturing industry collapsed.

In more recent years, huge amounts of money have been paid for commercial FM licences; even low-power, restricted area licences have attracted enormous bids, making analysts wonder how on earth these stations can ever be a money-making proposition.

Today, the commercial stations have seen the error of their ways and have certainly not refused free DAB+ frequencies. In fact the broadcasting industry has been the main force in pushing government to allow DAB+ transmissions.

They did not want to be left behind (again!) in the digital race.

The advantages of DAB+ are irresistible; 15 – 25 audio services per DAB+ channel and better resistance to errors. There is one transmitter per DAB+ channel.

Many radio manufacturers are developing DAB+ sets which will be progressively marketed in the coming months. Commercial Radio Australia has been supplying manufacturers with disk copies of some transmissions. This is so they can test their designs on DAB+ to optimise the sound quality and to ensure the receivers at the edge of the coverage area mute quietly, unlike some DTV receivers.