TB 9-4920-364-24
EQUIPMENT REQUIREMENTS
calibration procedure. This equipment is issued with Secondary Transfer Calibration
Standards Set AN/GSM-286; AN/GSM-287 or AN/GSM-705. Alternate items may be used
by the calibrating activity. The items selected must be verified to perform satisfactorily
prior to use and must bear evidence of current calibration. The equipment must meet or
provide a four-to-one ratio between the standard and TI. Where the four-to-one ratio
cannot be met, the actual accuracy of the equipment selected is shown in parenthesis.
5. Accessories Required. The accessories required for this calibration are common
usage accessories, issued as indicated in paragraph 4 above, and are not listed in this
calibration procedure. The following peculiar accessories are also required for this
calibration: Level, Bench type (7902565); Pin, 1 in., number 14 or 16 gauge wire (two
required, fabricate locally).
Table 2. Minimum Specifications of Equipment Required
Manufacturer and model
Common name
Minimum use specifications
(part number)
AUDIO ANALYZER
Range: 60 to 75 Hz
Boonton, Model 1121 (1121)
Frequency response: 0.25%
AUTOTRANSFORMER
Range: 105 to 125 V ac
General Radio, Model
1%
W10MT3AS3 (7910809)
Accuracy:
CALIBRATOR
Range: 0.84 to 48.0 mV dc
Fluke, Model 5720A (5700A)
0.33%
(p/o MIS-35947)
Accuracy:
FREQUENCY COUNTER
Range: 14.20 to 14.30 ms
Fluke, Model PM6681/656
0.025%
(PM6681/656)
Accuracy:
Range: 125 to 135 V ac;
Hewlett-Packard, Model 3458A
29 mV dc
(3458A)
1%
Accuracy:
A
Biddle-Gray, Model 71-631
RESISTANCE STANDARD
Range: 0 to 110,000
0.03%
(7910328)
ccuracy:
Range: 70 to 85 F
Azonix, Model A1012 (MIS38958)
THERMOMETER
1%
Accuracy:
CALIBRATION PROCESS
6. Preliminary Instructions
a. The instructions outlined in paragraphs 6 and 7 are preparatory to the calibration
process. Personnel should become familiar with the entire bulletin before beginning the
calibration.
b. Items of equipment used in this procedure are referenced within the text by common
name as listed in table 2.