3. VGA Level Check and Adjustment (KLM-662)

Turn off power end then on pressing number keys [7] and

[8] and Test Mode becomes 2.

Oscillating voice is displayed on LED Display with any

single key being played under this mode.

Note: it must be Test Mode 2 though voice displaying is

not required.

1) Select Program number 11.

2) Connect an Oscilloscope to [TP-SG] (GND side –

(TP-AGJ ) and observe amplitude of output waveform.

3) Press C5 key and observe waveform described in Fig. 1.

4) Adjust Semi Fixed VRs (VR101 – VR801) of oscillating

voice (refer to Voice Display) to obtain waveform of

amplitude being 0.7VP-P.

 

6. Noise Level Check and Adjustment (KLM-662)

1) Select Program number 15.

2) Connect a Noise Meter to [TP-SGJ (GND side – [TP-

AG] ).

3) Press any single key and confirm value of the meter is

-15dbm.

4) Unless, adjust VR1 to obtain correct value.

 

7. DWGS Clock Check and Adjustment (KLM-661)

1) Connect a Frequency Counter to [TP-CLK] (GND side

to [TP-DG] ).

2) Confirm the counter value is in range of 6.395MHz –

6.405MHz.

3) Unless, adjust VR2 to obtain correct value.

 

 

 

Remarks: Allowance of deviation of each voice is under

40mV.

 

4. OSC 2 Level Check and Adjustment (KLM-662)

1) Select Program number 12.

2) Make same adjustment as VGA Level one.

3) Necessary Semi Fixed VRs for adjustment are among

VR105 – VR805 of oscillating voice, (refer to Voice

D i splay)

 

5. VCF Resonance Check and Adjustment (KLM-662)

1. Level

1) Select Program number 13.

2) Connect an Oscilloscope to [TP-SG]. (GND side to

[TP-AG J ]

3) Press any single key and confirm amplitude of output

waveform of each voice is 0.9VP-P, Unless, adjust Semi

Fixed VRs among VR103 – VR803 of oscillating voice.

 

Remarks: Allowance of deviation of each voice is under

40mVP-P.

 

8. Digital Delay MG-CLK Check and Adjustment

(K LM-775)

1) Select Program number 16.

2) Connect a Frequency Counter to [TP-CLK] (GND side

to [TP-AG) ).

3) Confirm the counter value is 20.0kHz. (Effective with

3 figures only,)

4) Unless, adjust VR3 to correct value.

5) After 3) is confirmed, select Program number 17.

6) Confirm the counter value is in range of 35.0kHz –

40.0k H z.

 

9. Digital Delay Output Waveform Center Position Check

and Adjustment (K LM-775)

1) Select Program number 17.

2) Connect an Oscilloscope to [TP-EXP] (GND side to

(TP-AGJ ). Adjust lit line of the Oscilloscope to 0 volt

line of the screen.

3) Press C5 key and confirm center of amplitude of output

waveform is on 0 volt line of the screen.

4) Unless, adjust VR2 to obtain correct position.

 

 

 

2. fo

1) Select Program number 13,

2) Connect Chromatic Tuner AT-12 to Output Jack of DW-8000.

3) Press any single key and confirm oscillation frequency of each voice on AT-12 Display is C (523Hz), 1 octave, 0 cent. 4) Unless, adjust Semi Fixed VRs among VR102 – VR802 of osculating voice.

 

Remarks: Allowance of deviation of each voice is 0 cent +

10 cent.

 

3. fc

1) Select Program number 14.

2) Connect Chromatic Tuner AT-12 to Output Jack of

DW-8000.

3) Press any single key and confirm oscillation frequency

of each voice on AT-12 Display is C (2093Hz), 3 octave, 0

cent.

4) Unless, adjust Semi Fixed VRs among VR104 -- VR804

of oscillating voice.

 

Remarks: Allowance of deviation of each voice is under

0 cent + 10 cent.

 

10. Digital Delay Feed Back Check and Adjustment

(K LM-775)

1) Select Program number 18.

2) Press C5 key and confirm if delayed sound lasts 2

seconds without no ringing.

3) Unless, adjust VR1. (Start to ring when turn to the right.

Turn to the left and adjustment point is where ringing

stops.)

4) After 2) is confirmed, select Program number 21.

5) Press C5 key and confirm if there is no ringing with

delayed sound.

 

11. Check and adjustment of keyboard after touch

effect

Purpose: This should be performed if the keyboard is

replaced or in other cases when it is necessary to assure

balanced response and compensate for differences in the

weight of individual keys.

1) Remove connector CN23 from KLM-759 and connect

a digital multimeter (DVM or other device that measures

impedance) to the 1-pin (output) and 3-pin (GND or

earth).