Matsushita Electric SX-KC211, Руководство по обслуживанию

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power switch. “SW & LED” is displayed on the LCD.
Figure-11
2. Press all the buttons on the Control Panel and confirm that all the
PERFORMANCE PADS LEDs light and sine wave is produced.
- If an LED fails to light or no sound is produced, the cause
may be a defective switch or a break in the surrounding
circuit, etc.
- After all the buttons (except PLAY ) have been pressed, all the
PERFORMANCE PADS LEDs blink several times.
7.3. LCD module test
1. Press and hold the two G keys shown below, and then turn on the
power switch.
Figure-12
2. All the dots light on and off three times. All characters are
displayed in the text display area.
- If the correct display is not shown during these tests, the LCD
or LCD drive circuit may be defective.
8. PRECAUTIONS BEFORE SERVICING
8.1. Precautions for measuring of the output waveforms
1. The waveform was measured with a “National Digital Storage
Oscilloscope VP-5730A”. Therefore the waveforms of musical
tone signals shown may differ somewhat due to the difference in
the timing of triggering.
2. Since the 1/10 test probe is used, the indicated voltage value on
the bottom part of each waveform illustration is 1/10 of the actual
value (e.g. 0.2 V/cm should be 2.0 V/cm).
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