ACCEPTANCE TESTING
5-15
Audio generator frequency
This is a functional check only. The Audio generator frequency is derived digitally and provided
that the hardware is operational its accuracy will be maintained. The instrument’s internal
reference frequency is checked elsewhere. This check is listed at this point as it is one of the AF
generator tests, but it should be carried out after the UUT audio frequency meter has been checked
(see AF input tests; AF frequency meter).
Specification
Frequency accuracy:
0.01 Hz frequency standard 180 Hz
0.1 Hz ± frequency standard >180 Hz
(1) Refer to Results table 5-16 on page 5-36. Connect the UUT AF GEN OUT socket to the
UUT AF INPUT socket.
(2
) Set the UUT to [AF TEST], [AF Filter], [50 kHz LP] to set the Audio Input filter to 50 kHz
Lowpass.
(3) Set [Audio Gen], [LEVEL] 1 V, [FREQ] 10 Hz. Audio generator 2 should be switched OFF.
Check that the frequency indicated on the UUT audio counter is within the limits shown in
Results table 5-16. Repeat with the remaining frequencies shown in the table.
(4) Refer to Results table 5-17 on page 5-37. Repeat checks with AF GEN 2.
Kommentare zu diesen Handbüchern