A.W.A. RADIOLA 5

The Radiola 5 is a battery/mains portable radio that covers the broadcast band. It was made by A.W.A. (Amalgamated Wireless Australasia) as the model 555P, and has a blue ARTS&P label with dark blue writing, which dates it as 1955 to 1960. It is a 5 valve super heterodyne broadcast band receiver that will run off batteries or the mains. The plastic case is maroon and cream with a handle. Inside the cabinet is a mains cord and battery clips which allow fixed or portable use. The mains requirement is 240 volts 50 cycles, and the battery requirements are 7.5 volts and 90 volts. It runs well on 240 volts and is very loud. It picks up many local stations on the internal aerial. I have not tested it on batteries.

The dial scale is along the top at the front, and there is a pilot light behind this. The tuning knob is on the Right Hand Side and the Volume control is on the Left Hand side at the top. Under the Volume control is the ON/OFF switch, which also selects the power source. It is a 5 position rotary switch and is labelled ACTIVATE /AC /OFF /SAVE /FULL. On the back are sockets for an external aerial and earth.

The chassis is suspended from the top, just under the handle. The valves hang down, upside down, with clips to hold them in. Down one side is the power supply and control switch. There is room inside at the bottom for the batteries and the mains cord. The loop aerial is on the inside of the back cover, and the speaker is on the front. There is a 6X4 for the AC rectifier, a 3V4 audio output, a 1S5 audio pre amp/detector, a 1T4 IF amplifier, and a 1R5 oscillator/mixer. The IF frequency is 455kcs.

It was acquired in a dirty but non working condition. The upside down chassis was very clean and all parts except batteries were there. I replaced the broken dial cord, which was a bit tricky to get working properly. I also replaced all the paper capacitors. I checked all the valve filaments for continuity which were all good and replaced the burnt out pilot lamp. I then slowly powered it up through a VARIAC until I could see that the filament voltage was normal and the HT begin to rise. The radio worked, so I did not touch the IF or RF tuning. It has plenty of audio output and the internal aerial works well. After a few hours, it began to crackle, which turned out to be a noisy mica capacitor from the audio preamp anode to ground. I replaced this and it has worked nicely ever since.

A fine example of a late model Australian made battery portable.

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