TB 9-6625-2288-24
IDENTIFICATION AND DESCRIPTION
1. Test Instrument Identification.
This bulletin provides instructions for the
calibration of Electronic Voltmeters, AN/URM-145D (ME-247D/U) (Millivac Instruments,
Model MV-828A). TM 11-6625-524-14-4 and manufacturer's manual 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 indicated 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 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.
Performance specifications
Voltage ranges
Range accuracy
(V)
(FS)
Test instrument parameters
AN/URM-145D (ME-247D/U)
0.003 to 3
5%
20 kHz to
200 MHz
10%
200
to
400 MHz
(Millivac Instruments, Model
0.001
10%
20 kHz to
200 MHz
MV-828A)
15%
200
to
400 MHz
EQUIPMENT REQUIREMENTS
4. Equipment Required. Table 2 identifies the specific equipment to be used in this
calibration procedure. This equipment is issued with Secondary Transfer Calibration
Standards Set AN/GSM-287 or AN/GSM-705 and Secondary Reference Calibration
Standards Set, NSN 4931-00-621-7878. 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 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 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 this
calibration procedure.