TB 9-6625-1878-40
The equipment must meet or exceed the minimum use specifications listed in table 2. The
accuracies listed in table 2 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: Null Detector General Radio, Model 1232A (8616466-1) and Phase
Compensator ESI, Model PC874 (MIS-10242).
Table 2. Minimum Specification of Equipment Required
Manufacturer and model
Common name
Minimum use specifications
(part number)
DECADE TRANSFORMER
Range: 0.0099900 to 1.0000099
ESI, Model DT72A (7915908)
Accuracy: 2.5 ppm
Range: 10 V, 50 Hz and 1 kHz
General Radio, Model 1311A (7910432)
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 manufacturers' manual for this TI.
d. Unless otherwise specified, all controls and control settings refer to the TI.
7. Equipment Setup
WARNING
HIGH VOLTAGE is used or exposed during the performance of
this calibration.
DEATH ON CONTACT may result if
personnel fail to observe safety precautions.
REDUCE
OUTPUT(S) to minimum after each step within the
performance checks where applicable.
other models).
b. Energize equipment and allow sufficient time for temperature stabilization.
