Operating instructions

OPERATING MANUAL 2945A
46882-311D 5-17
LF generator
C2591
DVM
AF INPUT AF GEN
OUTPUT
VOLTMETER
INPUT
TERMINALS
UUT
Fig. 5-13 Audio voltmeter level accuracy checks
(6) Set the UUT AF filter to 50 kHz LP.
(7) Set the LF generator to frequency 50 Hz level 1 V RMS (adjust until DVM indicates as close
to 1 V as possible). Check that the level indicated on the UUT voltmeter is within
±
3%
±
3 mV
±
resolution of the level indicated on the DVM.
(8) Repeat step 7 with LF generator frequencies of 100 Hz, 500 Hz, 10 kHz, 30 kHz and 50 kHz.
(9) Set the UUT AF input to DC coupled and substitute the LF generator with the DC power
supply. Set the external DVM to monitor DC volts.
(10) Set the DC supply to 25 V (adjust until DVM indicates as close to 25 V as possible). Check
that the level indicated on the UUT voltmeter is within
±
3%
±
3 mV
±
resolution of the level
indicated on the DVM. Repeat this step with the DC supply set to 50 V.
Audio oscilloscope
Specification
Voltage accuracy: ±5% of full scale DC to 50 kHz (3 Hz to 50 kHz AC coupled).
Ranges: 10 mV/div to 20 V/div in a 1, 2, 5 sequence.
Graticule: 10 horizontal by 6 vertical.
Test equipment
Description Minimum specification Example
LF generator 10 Hz to 20 kHz 10 mV to 12 V peak to peak. IFR 2965
DVM DC measurement and AC measurement 20 Hz to
20 kHz.
Solatron 7150+
DC PSU 0 to 30 V