TRANSMITTERS & TRANSCEIVERS

Type 643 Transmitter and CJP Receiver

DATE OF DESIGN

FREQUENCY RANGE

Tx - 1.5 to 24 MHz in 100 Hz steps.
Rx - 60 kHz to 30 MHz in 100 Hz steps.

POWER SUPPLIES

Complete 643-CJP equipment operting in Transmit A1CW mode with key down ie 100 W output:
a. 115 V + or - 8% AC 45 to 65 Hz or
b. 230 V + or - 8% AC 45 to 65 Hz or
c. 220 V + or - 6% AC 45 to 65 Hz or
d. 240 V + or - 6% AC 45 to 65 Hz 400 W or 735 VA maximum

Anti Condensation Heater Supply 115 or 230 V 40W

RANGE IN MILES.

TYPE OF SET (VALVES USED)

WAVEFORM

CW (A1)(A2J compatible)
MCW (A2, A2H, A2J)
DSB (A3)(A3A, A3H compatible)
SSB (A3J, A3H, A3A) USB only.

ASSOCIATED WAVEMETER.

METHOD OF PRODUCING OSCILLATIONS

WHERE USED/FITTED

Type 643 and Outfit CJP have been introduced into the fleet to replace Types 618 and 619 and Outfits, CAS and CAT and Receiver B40. Type 643 and Outfit CJP will be fitted as the main transmitter and receiver outfit in small ships e.g. Coastal Minesweepers.

Patrol Craft and MCMV's. Some of these fits will include two Outfit CJP.

Frigates and larger ships not fitted with Type 641 will be fitted with Type 643 and Outfit CJP as the emergency transmitter and receiver outfit. Metrological offices and general purpose bays in the MCO and other offices will also be fitted with Outfit CJP to replace Receiver B40.

FURTHER READING

PHOTOS, SCHEMATICS, DOCUMENTS

Details of Transmitter Type 643 and CJP.
Photograph of 643/CJP

NOTES.

Transmitter: BR 339, BR 341
Receiver: BR 340, BR 341