Korg EX-800 - 4. Master Oscillator Check and Adjustment; 5. Cutoff Check and Adjustment; 6. Resonance Check and Adjustment

4. Master oscillator check and adjustment:
Set tune knob to center and bend intensity to maximum.
Connect AT-12 to line out jack.
1) Select program no. 12.
2) Depress C3 key of POLY-800.
3) Confirm AT-12 indication of -1 OCT, C, Ocent. If nec
essary, adjust by turning KL-003 coil.
4) Next, push joystick to maximum upward pitch bend
position and confirm AT-12 reading of —1 OCT, G, +35
cents. Adjust KLM-601 VR2 if necessary.
5) At maximum joystick downward pitch bend AT-12 indi
cation should be -2 OCT, F, -35 cents. Adjust KLM-601
VR1 if necessary.
VR3 is a semi-fixed resistor to fix range of tune VR on
front panel.
Confirm +40 ~ +70 cents when tune VR is at # max
position.
Confirm -40 ~ -70 cents when tune VR is at b max
position.
If necessary, Adjust VR3.
5. Cutoff check and adjustment:
1) Select program No. 13.
2) Play C3 key of POLY-800
3) Connect oscilloscope to CN6A pin 1 and observe wave
form as in figure 1.
4) Adjust VR2 to obtain maximum waveform amplitude.
6. Resonance check and adjustment:
1) Select program no. 14.
2) Play C3 key of POLY-800.
3) Confirm that waveform is as shown in figure 2.
4) Adjust VR5 if necessary to prevent oscillation or to cor
rect waveform deviation from figure 2 example.
1.5msec (±20%)
0.1 V/div, 1msec/div
Fig. 2
Fig. 1
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Scan by Manual Manor
http://www.markglinsky.com/ManualManor.html