AN~PRC-74

1-2. System Operation a. Radio Set AN/PRC-74 or the AN/PRC- 74A (referred to as the radio set) is a light- weight, two-way communications set that is capable of receiving and transmitting voice and telegraph signals. Single-sideband (ssb) modulation is used for voice transmission, and continuous wave (cw) modulation is used for telegraph transmissions. The voice and telegraph receptions are demodulated and applied to a headset. The frequency range of the radio set for both receive and transmit modes of operation is between 2.000 megacycles (mc) and 11.999 mc.

b. The radio set may be portably operated or operated at a fixed station. When portably op- erated, the radio set is powered by either a rechargeable nickel cadmium storage battery pack, or a dry cell battery pack. An external battery charger and power supply assemblies are provided with the radio set when used at a fixed station. The power supply assembly allows the radio set to be powered by either the alter- nating current (ac) or direct current (dc) voltages available at the operating site. The external battery charger assembly is used to recharge the radio set batteries prior to using the radio set portably.

c. Three types of antennas are supplied with the radio set. Operating in the low end of the high frequency spectrum, the range of the radio set may be extended to hundreds of miles with the proper selection of frequency and antenna type. d. The operational features of the ANIPRC- 74 and AN/BRC-74A are identical except tha.t the A model has been modified by MWO 11- 5820-590-35/1 to permit operation with the AN/GRA-71 coder burst equipment. Refer to TM 11-5820-590-12 for operational procedures for coder burst operation. Refer to paragraph 1-59 of the technical manual for circuit differences between the two models.

Additional Files

TM 11-5820-590-35

DS, GS, AND DEPOT MAINTENANCE MANUAL

RADIO SET

AN/PRC-74

JULY 1966

PRC-74B AND C

TM 11-5820-590-12-1

OPERATOR'S AND ORGANIZATIONAL MAINTENANCE MANUAL (INCLUDING REPAIR PARTS AND SPECIAL TOOLS LISTS)

RADIO SETS AN/PRC-74B (NSN 5820-00-935-0030)

AN/PRC-74C (NSN 5820-00-177-1641);

POWER SUPPLIES PP-4514/PRC-74 (NSN 5820-00-942-0821)

PP-4514A/PRC-74 (NSN 5820-00-177-4581)

BATTERY BOXES CY-6121/PRC-74 (NSN 5820-00-908-3127)

CY-6314/PRC-74 AND CY-6314A/PRC-74 (NSN 5820-00-156-3934)

March 1967

TM 11-5820-590-35-1

DIRECT SUPPORT, GENERAL SUPPORT, AND DEPOT MAINTENANCE MANUAL

INCLUDING REPAIR PARTS AND SPECIAL TOOLS LISTS)

RADIO SETS AN/PRC-74B (NSN 5820-00-935-0030)

AN/PRC-74C (NSN 5820-00-177-1641);

POWER SUPPLIES PP-4514/PRC-74 (NSN 5820-00-942-0821)

PP-4514A/PRC-74 (NSN 5820-00-177-4581)

BATTERY BOXES CY-6121/PRC-74 (NSN 5820-00-908-3127)

CY-6314/PRC-74 AND CY-6314A/PRC-74 (NSN 5820-00-156-3934)

JULY 1968

PRC-74 Schematics

These are the missing schematics from the commonly found PRC-74B manual found on Google books

PRC-74 Instructions for adding Lower Sideband Support

Defines the process required to add Lower SSB (LSB) support for the PRC-74

James P Karlow