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Excessive level NG Insufficient level NG
(0.5 V/DIV, 1 mS/DIV) (0.5 V/DIV, 1 mS/DIV)+DC NG -DC NG
(0.5 V/DIV, 1 mS/DIV) (0.5 V/DIV, 1 mS/DIV)
6. DA check
Once again check the output waveform at the point that "5. GUIDE vol- ume check" is completed, to check the DC leakage and level.
In the following cases, the result is NG.
7. Output check Set the INST volume and MIC volume to 'maximum.'
Set the PHRASE SELECT volume to the '2' position.
Verify that "OVERDUB" and "REVERSE" are lit.
Verify that the output waveform is as shown in the diagram.
Note : The waveform will change slightly depending on the inac- curacy of the input function.
8. INST volume check Set the PHRASE SELECT volume to the '3' position.
Verify that "REVERSE" is dark and "TAP TEMPO" is lit red.
4. LEVEL volume check Connect your waveform measurement equipment as shown in the dia- gram below. Connect your oscilloscope to OUTPUT.
Input INST : 200Hz, square wave, 200 mVp-p MIC : 200 Hz, sine wave, -34 dBm
AUX IN : 200 Hz, square wave, 200 mVp-p, STEREO
Move the LEVEL volume to approximately the center position, and then back to the minimum position.
Move the LEVEL volume from 'minimum' to 'maximum', and verify that the waveform increases smoothly.
At this time, the MODE LEDs will light consecutively from "FLAT
AMP SIMULATE," following the waveform.
With the LEVEL volume at maximum, verify that the output waveform
is the same as shown in the diagram.
5. GUIDE volume check Move the GUIDE volume to approximately the center position, and then back to the minimum.
Move the GUIDE volume from 'minimum' to 'maximum,' and verify that the waveform increases smoothly.
At this time, the MODE LEDs will change successively from "FLAT
AMP SIMULATE," following the waveform.
With the GUIDE volume at maximum, verify that the output waveform
is the same as shown in the diagram.
(0.5 V/DIV, 1 mS/DIV)
200 Hz, 2.2 Vp-p ± 0.2 Vp-p (0.5 V/DIV, 1 mS/DIV)
200 Hz, 2.2 Vp-p ± 0.2 Vp-p
(0.5 V/DIV, 1 mS/DIV)
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(0.5 V/DIV, 1 mS/DIV)
1.2 Vp-p ± 0.2 Vp-p
(0.5V/DIV, 1mS/DIV)
(0.5V/DIV, 1mS/DIV)
Set the INST volume to 'minimum,' and slowly move it to 'maximum.'
Verify that the waveform increases smoothly.
Verify that that when the INST volume is at maximum, the waveform is
the same as shown in the diagram.
9. MIC volume check Set the PHRASE SELECT volume to the '4' position.
Verify that "TAP TEMPO" changes from red to green.
Set the MIC volume to minimum, and gradually move it to maximum.
Verify that the waveform increases smoothly.
Verify that "PEAK" lights as shown in the diagram.
Verify that when MIC volume is at maximum, the waveform is the same as shown in the diagram.
Connect a noise meter to OUTPUT, and verify that the reading is in the range of -1.0 dBm +/- 1.5 dBm.
10.MUTE check Set the PHRASE SELECT volume to the '5' position.
Verify that "TAP TEMPO" is dark and "LOOP QUANTIZE" is lit.
Verify that the output waveform is the same as the waveform shown in the diagram. Connect a noise meter to OUTPUT, and verify that the reading is in the
range of -22.0 dBm +/- 1.5 dBm.
11.AUX IN (NORMAL) check Set the PHRASE SELECT volume to the '6' position.
Verify that "LOOP QUANTIZE" is dark and "PHRASE USED" is lit.
Verify that the output waveform is the same as the waveform shown in the diagram.
12.AUX IN (FLAT AMP SIMULATE) check Set the PHRASE SELECT volume to the '7' position.
Verify that "PHRASE USED" is dark and "INST & MIC" is lit.
Verify that the output waveform is the same as the waveform shown in the diagram.
Press the FS-5U that is connected to the REVERSE jack, and verify that the waveform does not decrease.
13.AUX IN (CENTER CANCEL) check Set the PHRASE SELECT volume to the '8' position.
Verify that "INST & MIC" is dark and "NORMAL" is lit.
Verify that there is no longer an output waveform.
Note : If the waveform remains, it is possible that the CENTER CANCEL section is NG, or that there is a spot of solder on
the connector.
14.AUX IN (L ch) check Set the PHRASE SELECT volume to the '9' position.
Verify that "NORMAL" is dark and "CENTER CANCEL" is lit.
Input only the L channel to AUX IN.
Verify that the output waveform is the same as the waveform shown in the diagram.
Note : Verify that when compared with the output waveform of "12. AUX IN (FLAT AMP SIMULATE) check," the phase
is inverted.
(0.5V/DIV, 1mS/DIV)
0.6Vp-p ± 0.1Vp-p
(0.5V/DIV, 1mS/DIV)
2.0Vp-p ± 0.2Vp-p
(0.5V/DIV, 1mS/DIV)
1.8Vp-p ± 0.2Vp-p
(The start illuminating of the LED indication.)
(The LED indication will stay illuminated.)
