Click to view detailed pictures of the receiver.
Within the 3 groups there are small variations. The various models are identified by numerals placed in front of the C6940. The model pictured is a 10C6940 MF receiver, commonly called the main receiver in ship board installations.
These receivers are similar to and often mistaken for the Coastwatcher Sets, type C6770.
The MF receiver covers the range 100kc � 3.1 mc/s in the bands: 100 � 260kc, 230 � 665kc, 600 � 1700kc and 1500 � 3100kc.
The radio is a 6 valve superhet and is capable of AM, MCW and CW reception and is unusual in that it is designed to run off lead acid batteries � 6 volts for the LT and 120 volts for the HT.
The intermediate frequency is 95kc.
Audio output is available at 4 output impedances � 1.5, 13.5, 600 and 2000 ohms.
The following valves are used: RF 6U7G, Converter 6J8G, IF 6U7G, 2nd Detector 6G8G, Output 6U7G or 6V6 � depending on application. A 6U7 is used for the BFO.
This particular set came from Sydney Radio, VIS at La Perouse. It came to this museum courtesy of the Telstra Museum, Bankstown. The shipping note on the receiver indicates it was repaired in 1985. It was released from La Perouse in 2006.
© Ian O'Toole, 2009. Page created: 26/01/07 Last updated: 4/12/2009