TB 9-4931-413-40
Table 2. Minimum Specifications of Equipment Required
Manufacturer and model
Common name
Minimum use specification
(part number)
SOUND-LEVEL CALIBRATOR
No substitute
General Radio, Model 1562-A (MIS-10219)
CALIBRATION PROCESS
6. Preliminary Instructions
a. The instruction 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. Unless otherwise specified, all controls and control settings refer to the TI.
7. Equipment Setup
NOTE
Steps a and b below pertain only to model 1551-C with ac
power supply.
a. Connect TI to 115 volt ac source.
b. Set TI power supply POWER switch to on (up) position.
NOTE
Step c below is for model 1565-A only; steps d and e below are
for battery-powered model 1551-C only.
c. Turn TI left-hand knob to BAT. Meter pointer will indicate in region marked BAT.
If not, replace batteries.
d. Energize TI by lifting microphone holder to vertical position.
e. Turn METER BATTERIES switch to FIL 1, FIL 2, and PL, respectively. Meter
pointer will indicate in region marked BAT. If not, replace appropriate batteries.
NOTE
Throughout this bulletin, references to model 1565-A panel
markings and values are enclosed in parenthesis.
