Panasonic SXPX554 - ELECTRONIC PIANO, Service Manual

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PCB TEST MODE Procedure
CPL
CPR
Control Panel buttons
LED lighting check Press and hold the two F keys shown below, and then turn on the
switch.
Press the buttons on the control and confirm that the corresponding
light.
Control Panel LED
display check Press and hold the two G keys shown below, and then turn on the
switch.
The numbers are displayed automatically and repeatedly on the display.
MKB
Keyboard ROM (IC1)
check Press and hold the two A keys shown below, and then turn on the
switch.
If the keyboard ROM (IC1) is OK, only the TOUCH SENSITIVITY LIGHT
flashes. If it is defective, the LEDs (LIGHT and NORMAL, or LIGHT,
NORMAL and HEAVY) flash.
9. PRECAUTIONS BEFORE SERVICING
9.1. 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).
3. To measure the waveforms, first set this unit to the service
diagnostic mode (refer to “Wave ROM check on SELF-
DIAGNOSTIC FUNCTIONS ”). The WAVE ROM output will then be
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