TB 9-6625-1185-24
Standards Set AN/GMS-286, 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 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.
Table 2. Minimum Specifications of Equipment Required
Minimum use
Manufacturer and model
Common name
specifications
(part number)
AUTOTRANSFORMER
Range: 115 V ac
Ridge, Model 9020A
Accuracy: 1%
(9020A)
Range: 23 to 1000 V dc
Hewlett-Packard, Model 3458A
Accuracy: .5%
(3458A)
RESISTANCE STANDARD
Range: 10,000 megohms
Penn Airborne
Accuracy: 1.25%
NO. 1
(MIS 10412-4)
RESISTANCE STANDARD
Range: .095 to 1
Biddle-Gray, Model 71-631
NO. 2
megohms
(7910328)
Accuracy: 1.25%
1
RESISTANCE STANDARD
Range: 1 to 10 megohms
Beckman, Model CR10M
Accuracy: 1
NO. 3
(8598965)
RESISTANCE STANDARD
Range: 100 megohms
Beckman, Model CR100M
Accuracy: 1.25%
NO. 4
(8598966)
RESISTANCE STANDARD
Range: 1000 megohms
Beckman, Model CR1000M
Accuracy: 1.25%
NO. 5
(8579478)
VOLTAGE DIVIDER
Range: 1000 to 2550 V dc Fluke, Model 80E10
Accuracy: .5%
Combined accuracy of resistance standards no. 2 and resistance standards no. 3 is 1.25%.
1
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 and item identification number 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 these TI's.