Yamaha i88x Service Manual page 53

6-11Turn the [GAIN CH1] knob full clockwise for the
maximum volume level and apply a signal(-34dBu)
to the INPUT 1 jack.
6-12Turn the [GAIN CH2] knob full clockwise for the
maximum volume level and apply a signal(-34dBu)
to the INPUT 2 jack.
6-13Turn the [GAIN CH3] knob full clockwise for the
maximum volume level and apply a signal(-20dBu)
to the INPUT 3 jack.
6-14Turn the [GAIN CH4] knob full clockwise for the
maximum volume level and apply a signal(-20dBu)
to the INPUT 4 jack.
6-15Turn the [GAIN CH5/6] knob full clockwise for the
maximum volume level and apply a signal(-20dBu)
to the INPUT 5 jack.
6-16Turn the [GAIN CH5/6] knob full clockwise for the
maximum volume level and apply a signal(-20dBu)
to the INPUT 6 jack.
6-17Turn the [GAIN CH7/8] knob full clockwise for the
maximum volume level and apply a signal(-20dBu)
to the INPUT 7 jack.
6-18Turn the [GAIN CH7/8] knob full clockwise for the
maximum volume level and apply a signal(-20dBu)
to the INPUT 8 jack.
[Check Item]
6-1 Make sure that the Peak LED 1 lights up.
Lower the input signal level to +20dBu and confirm
that the Peak LED 1 is turned off perfectly at that
time.
6-2 Make sure that the Peak LED 2 lights up.
lower the input signal level to +20dBu and confirm
that the Peak LED 2 is turned off perfectly at that
time.
6-3 Make sure that the signal(+4+/-2dBu, 10K ohm
load) is output from the OUTPUT 1 jack correctly.
Also confirm that the distortion rate is 0.01% or less
at that time.
Change the frequency of input signal to 20Hz and
make sure that the output signal level stays in the
range of +/-1dB against the standard level at 1KHz.
Also change the frequency to 20KHz, make sure of
the same level as above.
Make sure that the signal level of OUTPUT 2 is -
80dBu or less.
Make sure that the signal(-6+/-2dBu, 33K ohm load)
is output from the HP L.
Also confirm that the distortion rate is 0.01% or less
at that time.
Make sure that the signal level of HP R is -70dBu or
less.
6-4 Make sure that the signal(+4+/-2dBu, 10K ohm
load) is output from the OUTPUT 2 jack correctly.
Also confirm that the distortion rate is 0.01% or less
at that time.
Change the frequency of input signal to 20Hz and
make sure that the output signal level stays in the
range of +/-1dB against the standard level at 1KHz.
Also change the frequency to 20KHz, make sure of
the same level as above.
Make sure that the signal level of OUTPUT 1 is -
80dBu or less.
Make sure that the signal(-6+/-2dBu, 33K ohm load)
is output from the HP R.
Also confirm that the distortion rate is 0.01% or less
at that time.
Make sure that the signal level of HP L is -70dBu or
less.
6-5 Make sure that the signal(+4+/-3dBu, 10K ohm
load) is output from the OUTPUT 3 jack correctly.
Also confirm that the distortion rate is 0.01% or less
at that time.
Change the frequency of input signal to 20Hz and
make sure that the output signal level stays in the
range of +/-1dB against the standard level at 1KHz.
Also change the frequency to 20KHz, make sure of
the same level as above.
Make sure that the signal level of OUTPUT 4 is -
70dBu or less.
6-6 Make sure that the signal(+4+/-3dBu, 10K ohm
load) is output from the OUTPUT 4 jack correctly.
Also confirm that the distortion rate is 0.01% or less
at that time.
Change the frequency of input signal to 20Hz and
make sure that the output signal level stays in the
range of +/-1dB against the standard level at 1KHz.
Also change the frequency to 20KHz, make sure of
the same level as above.
Make sure that the signal level of OUTPUT 3 is -
70dBu or less.
6-7 Make sure that the signal(+4+/-3dBu, 10K ohm
load) is output from the OUTPUT 5 jack.
Also confirm that the distortion rate is 0.01% or less
at that time.
Change the frequency of input signal to 20Hz and
make sure that the output signal level stays in the
range of +/-1dB against the standard level at 1KHz.
Also change the frequency to 20KHz, make sure of
the same level as above.
Make sure that the signal level of OUTPUT 6 is -
70dBu or less.
6-8 Make sure that the signal(+4+/-3dBu, 10K ohm
load) is output from the OUTPUT 6 jack correctly.
Also confirm that the distortion rate is 0.01% or less
at that time.
Change the frequency of input signal to 20Hz and
make sure that the output signal level stays in the
range of +/-1dB against the standard level at 1KHz.
Also change the frequency to 20KHz, make sure of
the same level as above.
Make sure that the signal level of OUTPUT 5 is -
70dBu or less.
6-9 Make sure that the signal(+4+/-3dBu, 10K ohm
load) is output from the OUTPUT 7 jack correctly.
Also confirm that the distortion rate is 0.01% or less
at that time.
Change the frequency of input signal to 20Hz and
i88X
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