Differences Between Models - TM-11-5820-477-300013

TM 11-5820-477-30

1-9. Differences Between Models

a. Local control units C-2329A/GRA-39, C-2329B/GRA-39 and C-2329C/GRA-39, and remote control units

C-2328A/GRA-39, C-2328B/GRA-39 and C-2328C/GRA-39 each have a call lamp on the front panel with an

associated control relay inside the housing, and radio frequency interference (RFI) filtering capability. The

C-2328A/GRA-39 and C-2329A/GRA-39 (comprising AN/GRA-39A), and the C-2328C/GRA-39 and C-2329C/

GRA-39 (comprising AN/GRA-39C), each have a sealed RFI filter assembly consisting of capacitors and

inductors. The C-2328B/GRA-39 and C-2329B/GRA-39 (comprising AN/GRA-39B) each have a sealed RFI filter

assembly consisting of capacitors and resistors. The basic model (AN/GRA-39) has no call lamp or RFI filtering.

b. The basic and A- models have identical wiring. The B- model component boards Al 02 and A201 have a

different printed wiring layout, resulting in different wire routing from P102 and P201 to the circuit boards. The C-

model is identical to the B- model.

c. The basic and A- models have been modified to add a 560-ohm resistor (R123) to improve monitoring when

Radio Set AN/PRC-25 is operated in the SQUELCH mode. This resistor was already a component of the B- and

C- models.

1-10. Equipment Data

Refer to TM 11-5820-477-12 for a description of the equipment and a listing of additional equipment required.

1-11. Safety, Care and Handling

Do not use ungrounded equipment. Throughout this manual are warnings, cautions and notes designed to protect

personnel and equipment. Learn the warnings on the warning page before attempting to install, operate or

perform maintenance on the equipment, and observe all warnings and cautions as you come upon them in the

text. Learn the applicable warnings and cautions associated with each item of additional equipment used in the

system, as outlined in their respective technical manual.

Section Ill. PRINCIPLES OF OPERATION

Para.

Page

Functioning of Remote Control Unit C-2328(*)/GRA-39 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5

Stage Analysis of Remote Control Unit C-2328(*)/GRA-39 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9

Battery Voltage Distribution, Remote Control Unit C-2328(*)/GRA-39 . . . . . . . . . . . . . . . . . . . . 1-11

Functioning of Local Control Unit C-2329(*)/GRA-39 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13

Stage Analysis of Local Control Unit C-2329(*)/GRA-39 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-16

Battery Voltage Distribution, Local Control Unit C-2329(*)/GRA-39 . . . . . . . . . . . . . . . . . . . . . . 1-18

1-12. Functioning of Remote Control Unit C-2329(*)/GRA-39 (figures 1-3 and 1-4)

NOTE

The following discussion applies to all models of Control, Radio Set C-2328(*)/GRA-39,

except where noted.

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