CHAPTER 1 INTRODUCTION - TM-11-6625-542-14-10008

TM 11-6625-542-14-1

CHAPTER 1

INTRODUCTION

Section I. GENERAL

38-750.

1-1. Scope

b. Report

Packaging

and

Handling

This manual describes Electronic Marker Generator

Deficiencies. Fill out and forward DD Form 6 (Packaging

AN/USM-108A (fig. 1-1) and provides instructions for

Improvement Report) as prescribed in AR 700-

operation, cleaning, troubleshooting, testing, and

58/NAVSUPINST 4030.29/AFR 71-13/MCO P4030.29A,

repairing the equipment. It also lists tools, materials, and

and DSAR 4145.8.

test equipment required for organizational and general

c. Discrepancy in Shipment Report (DISREP) (SF

support maintenance. No direct support maintenance is

361). Fill out and forward Discrepancy in Shipment

authorized for the equipment.

Report (DISREP) (SF 361) as prescribed in AR 55-

1-2. Indexes of Publications

38/NAVSUPINST

4610.33A/AFR

75-18/MCO

a. Refer to the latest issue of DA Pam 310-4 to

P4610.19B, and DSAR 4500.15.

determine whether there are new editions, changes, or

1-4. Administrative Storage

additional publications pertaining to the equipment.

For procedures, forms, and records, and inspections

b. Refer to DA Pam 310-7 to determine whether

required during administrative storage of this equipment,

there are modification work orders (MWO's) pertaining to

refer to TM 740-90-1.

the equipment.

1-5. Destruction of Army Materiel

1-3. Forms and Records

Demolition and destruction of electronic equipment will

a. Reports of Maintenance and Unsatisfactory

be under the direction of the commander and in

Equipment. Maintenance forms, records, and reports

accordance with TM 750-244-2.

which are to be used by maintenance pertaining to the

personnel at all levels are listed in and prescribed by TM

Section II. DESCRIPTION AND DATA

(2) Microsecond markers at intervals of 1, 5, 10,

1-6. Purpose and Use

50, 100 and 500 microseconds.

Electronic Marker Generator AN/USM-108A is a portable

(3) Millisecond markers at intervals of 1, 5, 10, 50

instrument which provides an accurate and stable source

and 500 milliseconds.

of sine waves, trigger pulses and time markers. The

(4) One-second and five-second intervals.

wide choice of outputs available permits the use of the

(5) Trigger pulses at rates of 1Hz, 10Hz, 100Hz,

generator in a variety of laboratory and calibration

1KHz, 10KHz and 100KHz.

applications. It provides a source of calibrating signals

b. Crystal Oscillator.

for oscilloscope sweep circuits, oscillators and counters.

(1) Frequency: lMHz-10Hz.

The AN/USM108A can also be used as a source of

(2) Accuracy: approx. 0.001%.

trigger-rate pulses and as a time measuring device.

(3) Stability: within three parts per million per 24

Markers can be used separately or in combination

hours.

depending on the desired presentation or application.

c. Power Requirements: 105 to 125 volts ac, or

1-7. Tabulated Data

210 to 250 volts ac, 50 to 60 Hz, 240 watts power

a. Output Signals.

consumption at 117 volts.

(1) Sine waves of 5MHz, 10MHz, and 50MHz.

1-1