FM transmitters legal?


New elf
Mar 27, 2015
Golden Point, Ballarat Victoria
There seems to be a lot of restrictions around FM transmitters. Can anyone tell me what requirements the transmission/ transmitter must meet to be legal in Aus? Also how to choose frequency. Daytime a lot of channels free but in evening picking up on almost every FM channel. Some are hundreds of km away so I will not interfere with them but will their transmission interfere with mine?
Any comments would be appreciated.


I love blinky lights :)
Community project designer
Dec 27, 2010
The short answer is that for a transmitter to be legal it has a range of not more than about 1m. Even if you do the legal thing and get your broadcasting licence to broadcast over Xmas the 1m range that you are legally allowed to transmit isn't what you really want. The commonsense thing that is generally done is to pick a frequency that is blank and at least 100kHz away from anything local and broadcast on that. A car radio tends to have good reception so using a clock radio or something with a fairly average receiver is a better indication of what radio can be picked up locally.
The legal 10uW transmitter won't interfere with anything beyond a few metres away but is next to useless.


Back again
Dec 5, 2012
Swansea, NSW
I use one of these from eBay and it works ok. It reaches around 100-150 mtrs clearly which is plenty. You can sometimes pick up the signal further down the road to around 500 mtr, but it's faint. We had a couple of families that lived close by and they would visit most nights and then return home to go to bed. The little ones were allowed to listen to my music on the radio as they went to sleep. The parents said Xmas time is the easiest their kids settled down to sleep! It's not the best unit, but does a good job on a budget. There are others referenced in the 101 manual that are better. There are threads and discussions about transmitters elsewhere in the forum too. I think I've read each of them at least twice because I too was concerned. Bottom line is were only transmitting our shows of a night usually. Although a number of people asked if I could transmit show details through the day (I haven't done that yet).