Amateurs experimenting with low frequency signal propagation often listen to the airfield and en-route aeronautical beacons that transmit between approximately 170 to 400 kHz to assess propagation conditions. Please be aware that as from 26th May Air Services Australia are closing down a large number of these beacons as part of the plan to make GPS the primary means of air navigation and to minimise the cost of maintaining ground based navigation beacons. A full list of closures is too long to mention here, but the main NDB beacon closures in WA are Caversham, Clackline, Ballidu, Balgo Hill, Jurien Bay, Parkerville, Pingelly, Morawa and Cocos Island. Beacons remaining active in this area include Jandakot, Busselton and (probably) RAAF Pearce.
A full list can be found at http://www.flightsafetyaustralia.com/2016/05/switch-on-about-the-navaid-switch-off/
The source of this information is the latest issue of the Civil Aviation Safety Authority's Flight Safety Magazine.