Graeme −> Biography −> Graeme McRae biography −> 774 3LO Radio 


I read the article my dad wrote on 3LO.  Did you know this station is still known as 774 3LO?  In the year 2000, they started announcing their name as "774 ABC" but the official name is still 3LO.  774 is its frequency, in KHz.  Does this strike you as a strange number?  All our AM stations in the U S and A are multiples of 10 KHz.  This one is a multiple of 9 KHz.  I decided to investigate all the AM radio stations operated by the Australian Broadcasting Corporation in the state of Victoria. They are:

3RN, Melbourne, 621 KHz
3MT, Omeo, 720 KHz
3RN, Wangaratta, 756 KHz
3LO, Melbourne, 774 KHz
3GI, Sale, 828 KHz
3RN, Albury/Wodonga, 990 KHz
3PB, Melbourne, 1026 KHz
3WL, Warrnambool, 1602 KHz

Every one of 'em is a multiple of 9 KHz!  Maybe you know that if AM radio stations are separated from one another by 9 KHz, that they must avoid modulating their signal at a rate greater than 4.5 KHz to prevent the interfering with stations on adjacent frequency channels.  I don't think the ear can hear much difference between 4.5 KHz (Australia) and 5 KHz (USA), but it's interesting nonetheless.  By lowering their fidelity in this way, the Australians manage to pack about 10% more radio stations into the same spectrum.  If you bring a digital-tuned radio from the U.S. to Australia, it won't be able to pull in 3RN or 3LO very well, because these stations are almost midway between two pre-set frequencies.  I guess digital AM radios made for the Australian market would have the same problem operating in the U.S.