CHAPTER 10. CONTROL, RADIO SET C-618/FR-93 AND CONTROL, RADIO SET C-7515/FRC-93

TM 11-5820-554-12

CHAPTER 10

CONTROL, RADIO SET C-618/FR-93 AND CONTROL, RADIO SET C-7515/FRC-93

Section I. INTRODUCTION

10-1. Description

Control, Radio Set, C 6118/FRC-93 (Collins 312B-

to 30 MHz. The phone patch uses circuitry which

and Control, Radio Set C-7515/FRC-93 (Collins

allows vox phone patch operation. It may also be

312B-5) will be referred to as the Collins 312B-4

switched manually if desired. The vfo used in the

and the Collins 312B-5 station controls (fig. 10-1).

Collins 312B-5 is a 70K-2 oscillator which is the

Each contains a directional coupler, wattmeter, a

same as that used in the Collins KWM-2/2A.

permanent magnet (pm) speaker, a phone patch, and

Switching circuits are provided to allow the

appropriate switching circuitry. The same types of

operation of Collins KWM-212A on different

directional coupler, wattmeter, phone patch, and

transmit and receive frequencies or transmit-receive

speaker are used in both the Collins 312B-4 and

operation on the same frequency using either vfo.

312B-5. In addition, the Collins 312B-5 contains a

(Fig. 10-2) shows the location of external

variable-frequency oscillator to provide separate

connections to the Collins 312B-5. The Collins

transmit and receive frequencies when used with the

312B-4 is similar except for the absence of vfo

Collins KWM-2/2A. The wattmeter indicates power

connections. Items furnished with each equipment

levels within the ranges of

are listed in table 10-1.

0 to 200 or 0 to 2,000 watts, forward or reflected. It

is accurate to within +5 percent over the range of 2

Figure 10-1.

Collins 312B-4 and Collins 312B-5 station controls, front panel view operating controls.

10-1