Operating instructions
ACCEPTANCE TESTING
5-18 46882-311D
LF generator
C2591
DVM
AF INPUT AF GEN
OUTPUT
VOLTMETER
INPUT
TERMINALS
UUT
Fig. 5-14 Audio oscilloscope check
(1) Refer to Results table 5-27 on page 5-40. Connect the equipment as shown in Fig. 5-14,
connecting to the AF input of the UUT.
(2) Set the UUT to [AF TEST], [Scope/Bar], [Scope], [AC DC] set to AC coupling. Set the
Scope timebase to 200
ยต
s/div.
(3) Set the LF generator to provide 1 kHz at each of the levels shown in Results table 5-27, at the
same time selecting the relevant vertical scale on the UUT. In each case adjust the LF
generator level until the trace occupies the full six divisions. Set the DVM to measure Volts
AC. Note the level on the DVM and check that it lies within the limits shown in the table.
(4) Disconnect the LF generator.
(5) Set the UUT oscilloscope to 5 V/div and the AF input to DC coupled. With no signal applied
use the front panel SCOPE position control to set the trace onto the bottom graticule line.
(6) Set the DVM to measure DC volts.
(7) Connect the DC supply in place of the LF generator and adjust its level until the oscilloscope
trace sits on the graticule line two divisions down from the top of the display. Check that the
DVM indicates a level within the limits shown in the above table.
(8) Temporarily remove the DC PSU, set the UUT oscilloscope to 10 V/div and use the front
panel SCOPE position control to set the trace onto the bottom graticule line. Reconnect the
DC PSU and adjust its level until the oscilloscope trace sits on the graticule line two divisions
up from the bottom of the display. Check that the DVM indicates a level within the limits
shown in the above table. Repeat for the final range shown in the above table but this time
adjusting the DC PSU level until the trace sits on the graticule line 1 division up from the
bottom of the display.
(9) Remove the DC PSU and reconnect the LF generator. Set the DVM to measure Volts AC.
(10) Refer to Results table 5-28 on page 5-41. Set the UUT to 1 V/div, 50 ms/div.
(11) Set the LF generator to the first frequency shown in Results table 5-28 at the same time
selecting the relevant timebase on the UUT. Adjust the LF generator level until the trace
occupies the full six divisions. Note the level on the DVM and check that it lies within the
limits shown in the table.