TB 9-6660-270-50
SECTION I
IDENTIFICATION AND DESCRIPTION
This bulletin provides instructions for the
1. Test Instrument Identification.
calibration of Aneroid Barometers ML-102( ), ML-332/TM, ML-333/TM, and FA112150.
TM 11-427, TM 11-2421, MIL-B11818B, and MIL-B-11839B were used as the prime data
sources in compiling these instructions. The equipment being calibrated will be referred to
as the TI (test instrument) throughout this bulletin.
a. Model Variations. Variations among models are described in text.
b. Time and Technique. The time required for this calibration is approximately 2
hours, using the physical technique.
2. DA Form 2416 (Calibration Data Card)
a. Forms, records, and
reports required for calibration personnel at all
levels are
prescribed by TB 750-25. DA Form 2416 must be annotated in accordance with TB 750-25
for each calibration performed.
b. Adjustments to be reported on DA Form 2416 are designated (R) at the end of the
sentence in which they appear. When adjustments are in tables, the (R) follows the
designated adjustment. Report only those adjustments made and designated with (R).
3. Calibration Description. TI parameters and performance specifications which
pertain to this calibration are listed in table 1.
Table 1. Calibration Description
Test instrument parameters
Performance specifications
Vacuum and pressure
Range: 540 to 1085 mbar, 22 to 31.5 in. Hg
Accuracy:
540 to 745 +2.0 mbar
745 to 850 1.6 mbar
850 to 925 1.0 mbar
925 to 1085 0.6 mbar
22 to 31.5 0.0095 in. Hg
Repeatability
0.8 mbar (ML-102( ))
0.3 mbar (ML-332 and ML-333)
SECTION II
EQUIPMENT REQUIREMENTS
4. Equipment Required. Table 2
identifies the
specific equipment to be
used in this
calibration procedure. This equipment is issued with Secondary Reference Calibration
Standards Set NSN 4931-00-621-7878. 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 listed in table 2. The
accuracies listed in table 2 provide a four-to-one ratio between the standard and TI. Where
2