TRANSMITTERS & TRANSCEIVERS

CNS 1 Transmitter

DATE OF DESIGN

1940

FREQUENCY RANGE

Transmitter - 8-20 Mc/s covered in four bands
a. 7.3-9.7 Mc/s
b. 9.25-12.3 Mc/s
c. 12-16 Mc/s
d. 15.5-20.6 Mc/s

NOTE: The frequency range of the TW12 is 375-500kc/s, and 1200-3000kc/s in seven pre-selected frequencies.

Receiver - 8-20 Mc/s covered in two bands
a. 8-13 Mc/s
b. 13-20 Mc/s

POWER OUTPUT

CW 40/50 Watts to aerial circuit; MCW 20/25 Watt to aerial circuit modulating at 80%.

RANGE IN MILES.

From 200 miles to potentially world wide at times.

TYPE OF SET (VALVES USED)

Standard superhet receiver with 6 valves
a. HF amplifier
b. Frequency changer
c. IF amplifier - 600 kc/s IF
d. 2nd detector, AVC and LF amplifier
e. BFO
F. LF output valve

The receiver, like all others, radiated, but the radiations were curtailed to be .1microV/metre at 1 nautical mile.

WAVEFORM

ASSOCIATED WAVEMETER.

METHOD OF PRODUCING OSCILLATIONS

WHERE USED/FITTED

FURTHER READING

PHOTOS, SCHEMATICS, DOCUMENTS

NOTES.

The picture below is of the CNS1 with Aerial Tuning Indicator on top, the control panel in the upper cabinet followed by the CNS1 transmitter and then the CNS1 receiver. We apologise for the quality of the picture but it is all we have, even though we have the handbook.

This very small set - 1' 4" deep x 2' 4.75" high x 1' 2.5" wide was designed to be fitted with the Transmitter Type TW12 and its associated receiver the Type 394G. R/T could be used on this set but it was rarely (if ever) fitted for such. The CNS1 could be operated as a separate unit having its own source of supply voltages.

The drawing above is our block diagram of a large pull-out schematic of the total [as designed] system of both equipments working in unison together.