TB 9-6625-1998-24
IDENTIFICATION AND DESCRIPTION
1. Test Instrument Identification.
This bulletin provides instructions for the
calibration of Signal Generator, AN/URM-127 (SG-377/U) and AN/URM-127A (SG-
377A/U). TM 11-6625-683-14 was 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 within the text.
b. Time and Technique. The time required for this calibration is approximately 2
hours, using the dc and low frequency technique.
2. Forms, Records, and Reports
a. Forms, records, and reports required for calibration personnel at all levels are
prescribed by TB 750-25.
b. Adjustments to be reported 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
Frequency
Range: 20 Hz to 200 kHz
Accuracy: 2% indication
Range: 10 V ac
Output voltage
Accuracy: -30% to +20% FS
Range: 100 V to 10 V ac
Accuracy: 5% FS
Distortion1
1% maximum (AN/URM-127)
2% maximum (AN/URM-127A)
Frequency meter (AN/URM-127 only)
60 and 400 Hz l %
1Standard
limited not checked above 100 kHz.
EQUIPMENT REQUIREMENTS
calibration procedure. This equipment is issued with Secondary Transfer Calibration
Standards Sets AN/GSM-286, AN/GSM-287 or AN/GSM-705. Alternate items may be used
by the calibrating activity. The items selected must be verified to perform satisfactorily
prior to use and must bear evidence of current calibration. The equipment must meet or
