TM 11-7440-232-12/NAVELEX 0967-LP-275-5010
Section II. PREVENTIVE MAINTENANCE CHECKS AND SERVICES (Operator's)
To insure that the digital data modem is always ready for operation, you must do scheduled preventive
maintenance checks and services (PMCS). When you are doing any PMCS or routine checks, keep in mind the
WARNINGS and CAUTIONS about electrical shock and bodily harm.
2-5. PMCS TABLE
A PMCS table for Digital Data Modem MD-701(*)/UY appears at the end of this section. There are five categories
or intervals of PMCS: B, D, A, W, and M. They head the INTERVAL columns of the PMCS TABLE. A check mark in
one or more of the INTERVAL columns indicates the check and/or service that should be performed by the operator at a
a. B stands for Before. (B) PMCS should be performed BEFORE operation to make sure your equipment is ready
for your mission.
b. D stands for During. (D) PMCS is performed DURING operation. This will help you spot small troubles before
they become big problems.
c. A stands for After. (A) PMCS should be performed AFTER operation.
d. (W) PMCS stands for WEEKLY and (M) PMCS stands for MONTHLY. These are important preventive
maintenance checks and services you make at those intervals to keep serious problems from suddenly happening.
e. You should perform (W) PMCS as well as (B) PMCS if:
You are the assigned operator and have not operated the digital data modem since the last (W) PMCS.
You are operating the digital data modem for the first time.
f. If your equipment fails to operate, notify the proper personnel as directed in your station's Standard Operating
Procedure. Corrective action will be taken by the next level of maintenance personnel. No operator/crew/
troubleshooting is authorized for the M D-701 (*)/UY.
Use your PMCS table to get the number for the TM ITEM NO. column of DA Form 2404
(Equipment Inspection and Maintenance Worksheet.)
If your equipment MUST be in operation all the time, check and service those items that can be
checked and serviced without disturbing operation. Make the complete checks and services
when the equipment CAN be shut down.