General Description
ATR4B (RAAF) - Ident No:Y10D/70429
The ATR4 is a low power portable equipment to provide both AM and CW transmission and Reception. The units were produced by Radio Corporation (Victoria) during WW2 for the Royal Australian Air Force.
The units were supplied with a haversack for one man operation. The radio itself weighs 20lbs, appx 9kg.(This unit is based on the RC-16 which was first produced in 1939 for use by the Forests Commission of Victoria.)
Technical Data
The valve line-up for the receiver is as follows:
| 1D5G | RF Amp |
| 1C7G | Converter |
| 1D5G | IF Amp |
| 1D8G | 1st Audio/det/BFO |
| 1L5G | Audio Power Output |
The IF frequency is 455kHz.
The transmitter is a crystal controlled oscillator followed by a plate modulated power amplifier. The transmitter can only be operated on one frequency per band.
The bands are 3 - 4.8 and 4.8 - 7 MHz.
The speech amplifier and modulator consists of a pentode valve driving a class B amplifier stage, the later being the modulator.
The transmitter valve line-up is:
| 1L5G | Microphone Amp |
| 1J6G | Class B Modulator |
| 1J6G | RF Power Amp |
| 1H4G | Crystal Osc. |
The battery supply voltages are: A 3v, B 180-130v, C -7.5 to - 4.5.
The following currents are drawn:
SEND: A 2v @ 0.78A,B 180v @ 46ma (unmod) 56ma (mod)
RECEIVE: A 2v@0.58A, B 135v@16ma
These sets were popular for use as portable rigs by radio amateurs. Many went into commercial service with government agencies, the Forestry Commission of New South Wales being a case in point.
Note: This set was replaced after WW2 by the TRP-1.
