TB 9-4931-443-24
IDENTIFICATION AND DESCRIPTION
1. Test Instrument Identification.
This bulletin provides instructions for the
calibration of AC Precision Supply, N. H. Research Model SF 613-1. 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 Variation. Variations among models are described in text.
b. Time and Technique. The time required for this calibration is approximately 4
hours, using the dc and low frequency technique.
2. Forms, Records, and Reports
a. Forms, records, and reports required for calibration personnel at all level 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) will follow the designated
adjustment. Report only those adjustments made and designated (R).
3. Calibration Description. Test instrument parameters and performance specifications
which pertain to this calibration are listed in table 1.
Table 1. Calibration Description
Test instrument parameters
Performance specifications
Line voltage regulation
Satisfactory performance with any line voltage between 105 and 125 v ac
Range: 10 Hz to 100 kHz
Accuracy: 1% of setting
Distortion
Maximum of 0.05%, 50 Hz to 10 kHz and maximum of 1%, 10 kHz to 100 kHz
Stability
Drift is not more than 20 ppm after 2 minutes
EQUIPMENT REQUIREMENTS
calibration procedure. This equipment is issued with Secondary Transfer Calibration
Standards Set 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
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 the
calibration procedure.
