ACCEPTANCE TESTING
5-22
LF generator
C6040
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.
To Next Page
Loading...
