LESSON 2 - GENERAL INFORMATION
This lesson is written in three sections, 1 thru 3. Each section has a lesson exercise which
will require responses from you based on information presented in the lesson. If you are unable
to answer a question, return to the lesson material and read the portion of the lesson that pertains
to the question. The location of the correct answers to each lesson exercise will be specified at
the end of each exercise. You may write the answers to each question on the Lesson Exercise
Sheet and then check your answers with the exercise solutions. Refer to your tuning procedures
job aid card while you read this lesson.
SECTION 1. CABLE CONNECTIONS
a. AN/GRC-103 Applications. The ability of the AN/GRC-103 to process PCM signals
makes this radio set suitable for radio-relay applications. Radio repeaters are used at relay sites
and the function of a repeater is reception, amplification, reconditioning, and retransmission of
the original PCM signal. In 12-channel operation, the AN/GRC-103 receiver regenerates the
PCM signal while in 24-channel operation the multiplex equipment performs the signal
regeneration. As you learned in the previous lesson, the AN/GRC-103 may be used in any of the
(1) 12-channel PCM radio terminal.
(2) 12-channel PCM repeater.
(3) 12-channel radio-to-cable conversion PCM terminal.
(4) 24-channel PCM radio terminal.
(5) 24-channel PCM repeater.
(6) 24-channel radio-to-cable conversion PCM terminal.
During this lesson the applications and cable connections of a 12-channel PCM radio terminal
and 12-channel PCM repeater will be discussed. Applications and cable connections of the
remaining configurations may be found in TM 11-5820-540-12, Chapters 1 and 3.