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

In questo link sono elencati 851 modelli, di cui 470 con immagini e 365 con schemi.
Elenco delle radio e altri apparecchi della Astor (brand), Radio Corporation Pty., Ltd.; Melbourne