Sony DVCAM DSR-50, Service Manual, Page: 223 / 285

5-93
5. FS48 kHz Frequency Characteristic Check
Mode STOP
Signal Audio: 1 kHz, –4 dBu signal
10 Hz, –4 dBu signal
20 kHz, –4 dBu signal
AUDIO INPUT terminal (CH-1, 2)
Measurement point AUDIO OUTPUT terminal (CH-1, 2)
Measuring instrument Audio level meter
Specified value Difference in output level:
A = –2.0 dB to +1.0 dB
B = –1.0 dB to +1.0 dB
Switch setting
REC LEVEL CONTROL knob (Front panel) (CH-1 to CH-4)
................... The position at Recording and Playing Check
Menu setting (AUDIO SET menu)
AUDIO MODE ...................... FS48K
Checking method:
1) Enter 1 kHz, –4 dBu signal to the AUDIO INPUT terminal
(CH-1).
2) At this time, measure the output level on CH-1, and the
measured value is assumed to be “a” (dBV).
3) Enter 10 Hz, –4 dBu signal to the AUDIO INPUT terminal
(CH-1).
4) At this time, measure the output level on CH-1, and the
measured value is assumed to be “b” (dBV).
5) Enter 20 kHz, –4 dBu signal to the AUDIO INPUT terminal
(CH-1).
6) At this time, measure the output level on CH-1, and the
measured value is assumed to be “c” (dBV).
7) Obtain the difference A (dB) between output level “b” (dBV)
and “a” (dBV) to check that it satisfies the specified value.
A = b – a
8) Obtain the difference B (dB) between output level “c” (dBV)
and “b” (dBV) to check that it satisfies the specified value.
B = c – b
9) For the CH-2, perform checking in the same manner.
6. FS48 kHz Noise Level Check
Mode STOP
Signal Audio: No signal
Nothing is connected to the
AUDIO INPUT terminal (CH-1, 2)
Measurement point AUDIO OUTPUT terminal (CH-1, 2)
Measuring instrument Audio noise meter
(with A-weight filter)
Specified value –78 dBV or less
(A-weight filter ON)
Switch setting
REC LEVEL CONTROL knob (Front panel) (CH-1 to CH-4)
................... The position at Recording and Playing Check
Menu setting (AUDIO SET menu)
AUDIO MODE ...................... FS48K
Checking method:
1) Connect the audio noise meter to the AUDIO OUTPUT
terminal (CH-1), and turn the A-weight filter on.
2) At this time, measure the noise level to check that it satisfies
the specified value.
3) For the CH-2, perform checking in the same manner.