TB 9-4935-367-24
EQUIPMENT REQUIREMENTS
calibration procedure. This equipment is issued with Secondary Transfer Calibration
Standards Sets 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 the
calibration procedure. The following peculiar accessory is also required for this calibration:
voltage divider, 600
double banana plug to triple banana jack, Hewlett-Packard Model
11047A (7911560).
Table 2. Minimum Specifications of Equipment Required
Manufacturer and model
Common name
Minimum use specifications
(part number)
AUDIO ANALYZER
Range: 40 Hz to 600 kHz
Boonton, Model 1121 (1121)
Capability: < 0.3%
AUTOTRANSFORMER
Range: 105 to 125 V ac
Ridge, Model 9020A
(9020A),
Accuracy: 1%
FREQUENCY COUNTER
Range: 49.75 mS to 1,001,900 Hz
Fluke, Model PM6681/656
Accuracy: 0.05%
(PM6681/656)
Range: -35.5 to -36.5 V dc
Fluke, Model 8840A/AF05
(AN/GSM-64D)
Accuracy: 0.35%
TRUE RMS VOLTMETER
Range: 1.80 to 20.6 V ac
Fluke, Model 8922A/AA
(8922A/AA)
Accuracy: 0.5%
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.
c. Unless otherwise specified, verify the result of each test and, whenever the test
requirement is not met, take corrective action before continuing with the calibration.
Adjustments required to calibrate the TI are included in this procedure. Additional
maintenance information is contained in the manufacturer's manual for this TI.
d. When indications specified in paragraphs 8 through 12 are not within tolerance,
perform the power supply check prior to making adjustments. After adjustments are made,
