Communications/Electronics

1. Message Center.  The Battalion Message Center, now located at VCB, received 765 incoming messages and released 18 outgoing messages through the 4^th Marines Regimental Message Center.  Numerical codes, word codes, authentication tables, and Communication Operating Instructions were distributed as required.
2. Radio.  The radio section maintained a Battalion Tactical Net, a Base Defense Net (as required), and a Covered Regimental Net.  As a result of a COI change eliminating a previously assigned frequency, the Administrative Net between VCB and QTCB was discontinued.  A relay station was established at FSB Henderson to improve communications with Companies C and D, who were operating in that area.  The Regimental Brevity Code was declared unauthorized by the 3^rd Marine Division and was replaced by the KAC QAL numerical codes and authentication tables and the KAC PZ word codes for encrypting traffic between Companies and the Battalion.  The AN/PRC-88 provided reliable communications between Company Commanders and their Platoon Commanders, Squad Leaders, and 60mm Mortar Sections when occupying defensive positions.
3. Covered Circuits.  The Covered Circuit remained unchanged during this period with one KY-38 and one AN/PRC-77 in operation, and 22 KY-38’s and one AN/PRC-77 on hand.
4. Wire.  The Battalion switchboard at VCB employed three SB-22/PT switchboards serving 34 subscribers with two trunk lines to the 4^th Marines and one trunk line to Force Logistic Support Group B.  Hot lines were employed from the Battalion Combat Operations Center (COC) to the Vandegrift Installation Coordinator (VIC), the 4^th Marines COC and the Battalion S-4.  Telephones were installed at Ca Lu for use by Company A and at FSB Henderson for use by the 81mm Mortar Section located there.
5. Electronic Repair.  Work order forms have been locally prepared and distributed to the various sections within the Communications Platoon for use when turning in equipment.  The work order serves as a receipt for sections that have turned in equipment and provides a method of control for the maintenance section.  One AN/USM-50C oscilloscope, two PP-4567 battery chargers, and 27 IM-143 Radiac meters were submitted to FLSG-B for calibration.  Critical repair parts for this period were H-189 handset receiver elements.  Two technicians, one in MOS 5931 and the other in MOS 2815, reported for duty during this period.
6. Equipment Repaired.  The total essential and/or combat essential equipment deadlined and brought off deadline during the month was as follows:

ITEM                           To D/L            Off D/L

AN/PRC-25                         25                    19

`                                   AN/PRC-88                           3                      2

SB-22/PT                               1                      1

AN/PRC-41                           1                       1

AN/PRC-87                           1                       1

This page last corrected 5 September 2011