Yamaha n8 Service Manual page 85

Check that ST OUT level is as shown below at this time.
Unit: [dBu]
ST OUT
-5 ± 3 dB
Sleeve:
GND
Tip: output
Ring: input
1-2-9. Hi-Z
Set up as in the following table.
Input signal from CH 4 (n8)/CH 8 (n12) with unbalanced
system.
Turn on the Hi-Z switch of CH 4 (n8)/CH 8 (n12).
Check that the difference in output level when a 500 kΩ
resistor is connected in series to the signal line compared to the
output level before connecting the resistor is as follows:
Input CH4 (n8)/
GAIN PAD
CH8 (n12)
-25 dBu
MAX ON
(Unbalance)
1-2-10. INPUT B (CH 1-4 (n8)/CH 1-8 (n12))
Set up as in descriptions marked w and r in procedure 1-2-2.
Insert an empty plug, which has no wiring connection, to the
INPUT B of the input channels to be measured.
Check that there is no output from the ST OUT when the plug
is inserted.
1-3. Output system
1-3-1. Preparations
Set the n8 or n12 to AD/DA through (Output test mode) for test.
Refer to "2-12. AD/DA through connection" for details of
setup procedure and internal connection. (Page 78)
1-3-2. Gain (Output)
Set up controllers as follows.
GAIN Volume of CH 1 and 2:
C-R/AUX PHONES:
ON SW of CH 1 and 2:
PAD SW of CH 1 and 2:
ST OUT
INPUT
(LINE)
INPUT
LEVEL
L R
CH A 1 +10 +4 ± 2 *1 –
CH A 2 +10 – +4 ± 2 *1
5.1 k ohms
5.1 k ohms
ST OUT R ST OUT R
(input without resistor) (input with resistor)
+4 dBu
-6 ± 1 dB
(reference)
MIN
MAX
On
On
Unit: [dBu]
ST OUT AUX OUT
(RCA) (n12 only)
L R L R
*1
-7.8 ± 2 – +4 ± 2 *1 –
}
*3
!!4
*1
– -7.8 ± 2 – +4 ± 2 *1
*3
C-R OUT (n8)
INPUT INPUT
C-R OUT A-C (n12)
LEVEL
L R
CH A 1 +10 +4 ± 2 –
*1
CH A 2 +10 – +4 ± 2 *1
*1: Check that level differences between channels are as
follows:
Tolerance
2 dB or less
*2: Check that level differences between L/R channels are as
follows:
Tolerance
2 dB or less
*3: -7.8 dBu = -10 dBV
1-3-3. MUTE
Set up as in description marked !4 in procedure 1-3-2.
Execute SSP1-MUTE of the service check program. Check if
the corresponding output terminal is muted as in the following
table. Refer to "2-7. MUTE ON/OFF test" for service check
program. (Page 77)
Unit: [dBu]
OUTPUT
OUTPUT
LEVEL
TERMINAL
(With muting)
ST OUT
-90 or less
(LINE)
ST OUT
-90 or less
(RCA)
AUX OUT
-90 or less
(n12 only)
C-R OUT (n8)
-90 or less
C-R OUT A-C (n12)
C-R
-90 or less
PHONES
AUX
-90 or less
PHONES
· Use 12.7 Hz, -6 dB/oct LPF.
1-3-4. Frequency characteristics (Output)
Set up as in description marked !4 in procedure 1-3-2.
Check that the levels of each output when the frequency is 20
Hz and 40 kHz are within the range shown below compared
with the level when the frequency is 1 kHz.
Tolerance
Within +1/-3 dB
n8/n12
Unit: [dBu]
C-R AUX
PHONES PHONES
L R L R
-6.9 ± 2 – -6.9 ± 2 –
*2 *2
}
!!4
– -6.9 ± 2 *2 – -6.9 ± 2 *2
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