Frequency Characteristic Check - Sony DSR-45 Service Manual

DSR-45/45P
(2) –2dB Check
Mode
Signal
Measurement Point
Measuring instrument
Specified Value
Note 1: 0 dBu = 0.775 Vrms/balance
Note 2: 0 dBs = 0.775 Vrms
Switch setting
INPUT LEVEL select switch .......................... –2
AUDIO REC LEVEL control knob (CH-1 to 4)
.......... The position at –10 dB Check of E-E Level Check
Menu setting (AUDIO SET menu)
AUDIO MODE ................................................ FS32K
Checking method:
1) Enter 1 kHz, –2 dBs signal to the AUDIO IN terminal (CH-1).
2) Check at this time that the output of AUDIO OUT terminal
(CH-1) satisfies the specified value.
3) For the CH-2 to 4, make a checking in the same manner.
(3) +4dB Check
Mode
Signal
Measurement Point
Measuring instrument
Specified Value
Note 1: 0 dBu = 0.775 Vrms/balance
Note 2: 0 dBs = 0.775 Vrms
Switch setting
INPUT LEVEL select switch .......................... +4
AUDIO REC LEVEL control knob (CH-1 to 4)
.......... The position at –10 dB Check of E-E Level Check
Menu setting (AUDIO SET menu)
AUDIO MODE ................................................ FS32K
Checking method:
1) Enter 1 kHz, +4 dBs signal to the AUDIO IN terminal (CH-1).
2) Check at this time that the output of AUDIO OUT terminal
(CH-1) satisfies the specified value.
3) For the CH-2 to 4, make a checking in the same manner.
STOP
Audio: 1 kHz, –2 dBs signal
AUDIO IN terminal (CH-1 to 4)
AUDIO OUT terminal (CH-1 to 4)
Audio level meter
+2 to +6 dBu
STOP
Audio: 1 kHz, +4 dBs signal
AUDIO IN terminal (CH-1 to 4)
AUDIO OUT terminal (CH-1 to 4)
Audio level meter
+2 to +6 dBu

4. Frequency Characteristic Check

(1) 4CH mode Check
Mode
Signal
Measurement Point
Measuring instrument
Specified Value
Note 1: 0 dBu = 0.775 Vrms/balance
Note 2: 0 dBs = 0.775 Vrms
Switch setting
INPUT LEVEL select switch .......................... –10
AUDIO REC LEVEL control knob (CH-1 to 4)
.......... The position at –10 dB Check of E-E Level Check
Menu setting (AUDIO SET menu)
AUDIO MODE ................................................ FS32K
Checking method:
1) Enter 1 kHz, –10 dBs signal to the AUDIO IN terminal (CH-1).
2) Measure the output of AUDIO OUT terminal (CH-1) at this
time, and assume it to be "a" (dBu).
3) Enter 10 Hz, –10 dBs signal to the AUDIO IN terminal (CH-1).
4) Measure the output of AUDIO OUT terminal (CH-1) at this
time, and assume it to be "b" (dBu).
5) Enter 14 kHz, –10 dBs signal to the AUDIO IN terminal (CH-1).
6) Measure the output of AUDIO OUT terminal (CH-1) at this
time, and assume it to be "c" (dBu).
7) Calculate the difference A (dB) between output levels "b" (dBu)
and "a" (dBu) to check that it satisfies the specified value.
A (dB) = b (dBu) – a (dBu)
8) Calculate the difference B (dB) between output levels "c" (dBu)
and "a" (dBu) to check that it satisfies the specified value.
B (dB) = c (dBu) – a (dBu)
9) For the CH-2 to 4, make a checking in the same manner.
5-92
STOP
Audio: 1 kHz, –10 dBs signal
10 Hz, –10 dBs signal
14 kHz, –10 dBs signal
AUDIO IN terminal (CH-1 to 4)
AUDIO OUT terminal (CH-1 to 4)
Audio level meter
Difference in output level:
A = –2.5 to +1.5 dB
B = –1.5 to +1.5 dB