Mickey OZ AC/DC Mains

• alternative name: Radio Corp.of Australia

Astor Mickey OZ was a 5 valve, AC/DC mains powered superhet.

The early 1933 Astor OZ radios, September to November 1933, up to approximately serial number 460 were powered direct from the AC or DC mains without a power transformer. The valve filaments were connected in series with a 580 Ω across the incoming mains.

The loudspeaker field coil resistance was 1900 Ω and used back bias on the audio output valve. The speaker cloth had an embossed bell pattern. There was also a square edge around the front of the cabinet.

This was disastrous model because of overheating in the midget configuration. Many were sent back to Radio Corporation then reconfigured as a transformer set.  The mains tx was angled. To identify that it was officially done, the 1900 Ω field was changed to 1350 Ω and a wirewound 650 Ω resistor was put in series with the field and wrapped in a phenolic cover.

This AC/DC circuit was also used later in the Astor UZ console.

The Minnie Mouse Auditorium Speaker was available as an accessory for this radio.

It plugged into a socket on the rear and was switched into circuit by a rotary switch on the side of the radio. It is assumed a special knob was proved with the speaker to operate the switch on the side of the radio.

Later versions used a power transformer and several variations in circuit design and cabinet are known. See Astor OZ

Here you find 851 models, 466 with images and 359 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
All listed radios etc. from Astor (brand), Radio Corporation Pty., Ltd.; Melbourne