TB 9-6625-1980-24
EQUIPMENT REQUIREMENTS
calibration procedure. This equipment is issued with Secondary Transfer Calibration
Standards Set AN/GSM-287 or AN/GSM-705. Alternate items may be used by the
calibrating activity when the equipment listed in table 2 is not available. The items
selected must be verified to perform satisfactorily prior to use and must bear evidence of
current calibration. The equipment must meet or exceed the minimum use specifications
standard and TI. Where the four-to-one ratio cannot be met, the four-to-one 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 standard extender board, Fluke PN 1702-187344.
Table 2. Minimum Specifications of Equipment Required
Minimum use
Manufacturer and model
Common name
specifications
(part number)
AUTOTRANSFORMER
Range:
105 to 125 V ac
Ridge, Model 9020A
Accuracy: 1%
(9020A)
Range:
49.99 mV to 25.25 V
Hewlett-Packard, Model 3458A
Accuracy: 0.005%
(3458A)
10 to 1 MΩ
RESISTANCE STANDARD
Biddle-Gray, Model 71-650
Range:
Accuracy: 1%
(71-650)
SHUNT
Range: 0 to 100 mA dc
Guildline, Model 9711A
Accuracy: 0.01%
(7912323)
CALIBRATION PROCESS
6. Preliminary Instructions
a. The instructions outlined in this section 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 the manufacturer's manual for this TI.
d. When indications specified in paragraphs 8 through 14 are not within tolerance,
perform the power supply check prior to making adjustments. After adjustments are made,
