TB 9-4920-456-24
IDENTIFICATION AND DESCRIPTION
1. Test Instrument Identification.
This bulletin provides instructions for the
calibration of Transponder Test Set AN/APM-421. The manufacturer's manual was used as
the prime data source in compiling these instructions. The equipment being calibrated will
be referred to as the TI (test instrument) throughout this bulletin.
a. Model Variations. None.
b. Time and Technique. The time required for this calibration is approximately 11
hours, using the dc and low frequency and microwave techniques.
2. Forms, Records, and Reports. Forms, records, and reports required for calibration
personnel at all levels are prescribed by TB 750-25.
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
Multimeter function test
consisting of:
Ac voltage
Range: 100 to 126 V ac
Accuracy: 2% of digital voltmeter indication plus 2 V ac
Frequency: 400 Hz
Ac current
Range: 1.0 to 1.26 A
Accuracy: TI indication = digital voltmeter indication x 10 2%
plus 0.2A
Frequency: 400 Hz
Dc voltage
Range: 18, 28, and 35 V d c
Accuracy: 2% plus 0.1 V dc
Dc current
Range: 0.194 to 5.2 A
Accuracy: 2% plus 0.1 A
