Alesis E-DRUM TOTAL, Service Manual

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If there is no sound in any case, the error may be in the main chip or the line of AMP.
1. Only strike the drum
Check the signal of pin 75/76/78 in the IC201.
Strike the drum; Check the signal of pin 75/76/78 in the U10 .If the signal is normal, check the
relevant circuit elements of drum.
2. No sound all
a) Check the IIS bus in the main chip A2.
The signals are:
I2S CLK (IC201.1): 12MHz Square Wave.
I2S BCLK (IC201.144): 3.0MHz Square Wave.
I2S WS (IC201.143): 46.875 KHz Square Wave.
I2S DOUT (IC201.5): If playing pattern or striking drum, the signal is changed.
If the signal is not normal, check the line of main chip A2, such as AR208, check whether short cut
or open circuit, change A2 chip if necessary.
b) Check IC301 (PCM1754) and relevant circuit elements.
c) If above is ok, check the line of AMP.
The signals are:
¾
Check the signal of pin1/7 in IC302.
¾
Check the IC302.2/3/4/5
¾
Check the signal of pin1/7 in IC303/IC304. (phones output, in HEADPHONE board)
d) If the signals are ok, replace relevant IC.
3. No sound when striking drum
1. Check the relevant signal (IC401/402/403/404), when striking the drum, relevant pin has charge and
discharge signal, see below. If not, check the relevant circuit elements.
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