Section III. OPERATION UNDER USUAL CONDITIONS

TM 11-7440-232-12/NAVELEX 0967-LP-275-5010

Section III. OPERATION UNDER USUAL CONDITIONS

2-6. ASSEMBLY AND PREPARATION FOR USE

The digital data modem will be transported to the site and installed by maintenance personnel. Preliminary

adjustments and system-check will have been performed before you operate the equipment. Grounding and power

connections and system application strapping will have been made by maintenance personnel.

2-7. INITIAL CHECKS

You will be ready for operation after making the initial checks listed below.

· Digital data modem - Inspect your modem. Use the Components of End Item List (COEIL) in Appendix B to be

sure you have everything needed to operate the modem. Also look for damaged items. Report missing or

damaged material to the proper personnel.

· Power - Make sure 115-volts power connections are tight at the 115-volt ac power source.

· Grounding - Check the protective grounding connection. Look for a loose connection, and tighten if necessary.

2-8. OPERATING PROCEDURES

a. After the digital data modem has been installed and checked out for a particular system application, it is placed

in operation.

b. Simplified operating procedures are as follows: Set TRANS MODE, REC MODE, BIT RATE, AND ALARM

CUTOFF switches in accordance with the Standard Operating Procedures (SOP) of the day for the system application.

Then, turn the power supply switch to ON.

NOTE

Do not turn power supply to ON unless the transmitter branch and receive branch controls are

set for the assigned system application; otherwise, you will transmit at an unauthorized data

rate.

c. Operating Instructions - Turn on

Set transmitter TRANS MODE switch to NORM.

Set transmitter BIT RATE switch to LOW or HIGH bit rate in accordance with the stations SOP for the day.

Set limiter discriminator REC MODE switch to NORM.

Set decoder error detector BIT RATE switch to LOW or HIGH in accordance with the stations SOP.

Set digital receiver clock BIT RATE switch to 0.6, 1.2, or 2.4 in accordance with the stations SOP.

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