SECTION II CALIBRATION OF DIFFERENTIAL VOLTMETERS AN/USM-98 (J-F 801 AND 801R)

TB 9-6625-1866-50

AN/USM-98A and AN/ USM-98B (John Fluke Models 801B, 801BR, and 80 1B/AG) will be

referred to as UUT in section III.

c. Equipment and Accessory Identification. The equipment and accessories

referred to throughout this bulletin are identified in tables 1, 2, 6 and 7 and section IV.

d. Equipment Setup. Disconnect instructions are not contained in this bulletin.

5. Differences Among Models. Differential Voltmeter 801R is a rack-mounted version

of the 801. AN/USM-98 is the military designation for the 801. Differential Voltmeter

801B contains a standard cell; the 801B/AG contains a Zener diode. The 801BR is the rack-

mounted version of the 801B. AN/USM-98A is the military designation for the 801B and

801B/AG. The AN/USM-98B is similar to the 801B. Front panel designations may vary

among models.

SECTION II

CALIBRATION OF DIFFERENTIAL VOLTMETERS

AN/USM-98 (J-F 801 AND 801R)

6. Equipment and Accessory Required. Table 1 lists minimum use specifications of

equipment required for calibration performance checks and adjustments. Table 2 lists the

required accessory. Tables 1 and 2 are provided to assist in the selection of required

equipment and accessory. For specific item identification refer to section IV.

Table 1. Minimum Specifications of Equipment Required

Item

Number

Common Name

Minimum Use Specifications

RANGE: 105 to 125 vac

ACCURACY: 1%

DC VOLTAGE STANDARD

RANGE: 0 to 520 v

ACCURACY: 0.016%

Table 2. Accessory Required

Item

Number

Common Name

Description

CABLE

30-in., RG-58/U; double banana plug

terminations

7. Preliminary Procedure

NOTE

Personnel should familiarize themselves with the entire

bulletin prior to performing calibration.

a. With no power applied to UUT, mechanically zero meter, using meter mechanical

zero adjustment screw.