Alto L-6, Руководство по обслуживанию, Страница: 18 / 28

LEVEL LEDs will turned off, when turn MAIN MIX LEVEL pot clockwise to the
maximize, the LEVEL LEDs will be illuminated in sequence. test that whether the
relating LED is illuminated when the level of output signal reaches the exactly
value as LED shows . If so, test the maximize output level (before clipping) is
20dBu(±1dB) THD + N<0.1%.)
Adjust TRIM knob of CH 1 clockwise, PEAK LED will be illuminated (red). And
test all PEAK LEDs from CH 1 to CH6
3. frequency response test
When Test the inputs of LINE 1, LINE 2, LINE 3, LINE 4, LINE 5, LINE 6
separately as follows, the frequency response curve of MAIN MIX OUTPUT
(LEFT & RIGHT) (the preset of all knobs are the same as function test step 2.b)
a. Open S8RESP1.atl test procedure, press and release the LOW CUT switch, test
the frequency response curve of LINE 1, LINE 2 LINE 3, LINE 4 , please refer
to the following figure.
(Remark: don’t need to test L6 with this step)
Audio Precision 07/22/03 15:41:30
-50
+20
-40
-30
-20
-10
+0
+10
d
B
m
20 20k 50 100 200 500 1k 2k 5k 10k
Hz