CIRCUIT DESCRIPTION KEY MATRIX Tempo Volume Start/Stop Tempo Volume Synchro/ Down Down Fill-In Song Melody Tone Rhythm Bank On/Off CONCERT Fingered Normal Power Off Chord NOMENCLATURE OF KEYS F#3 G#3 A#3 C#4 D#4 F#4 G#4 A#4 C#5 D#5 F#5 G#5 A#5 G2 A2 C2 D2 C3 D3...
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CPU (LSI101: MSM6755B-06) The CPU contains a sound data ROM and a DAC (Digital to Analog Convertor), and it provides left and right channel sound waveforms in accordance with the pressed key and the selected tone. The following table shows the pin functions of LSI101. Pin No.
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POWER AMPLIFIER (IC101: LA4598) The power amplifier is a two-channel amplifier with standby switch. The following table shows the pin function of IC101. Pin No. Terminal In/Out Function Power GND Ground (0V) source Ch1 B.S. — Terminal for a bootstrap capacitor Ch1 OUT Channel 1 output +9V source...
INITIAL RESET CIRCUIT When batteries are set or an AC adapter is connected, the reset IC provides a low pulse to the CPU. The CPU then initializes its internal circuit. Battery Set Reset IC MSM 6755B-06 RE5VA35A LSI101 IC102 RESET TROUBLESHOOTING Nature of Trouble Faulty Block...
SCHEMATIC DIAGRAMS Main PCB KDM440-MA1M Notes: µF) 1. All capacitance values are indicated in "µF" (p=10 Ω, M=10 Ω). 2. All resistance values are indicated in "Ω" (k=10 — 9 —...
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Keyboard PCBs KDM6111K-KY1M/KY2M Notes: µF) 1. All capacitance values are indicated in "µF" (p=10 Ω, M=10 Ω). 2. All resistance values are indicated in "Ω" (k=10 — 10 —...
PARTS LIST CTK-480 Notes: This parts list does not include the cosmetic parts, which parts are marked with item No. "R-X" in the exploded view. Contact our spare parts department if you need these parts for refurbish. Prices and specifications are subject to change with- out prior notice.