NAD Masters M3, Руководство по обслуживанию, Страница: 18 / 59

2.Preamp operation flow
Power on
Amber LED change to
blue?
NO
Check FPP board
YES
Hear the relay’s click?
NO
Check 24V relay suply
Check U113,U108,U213,U208
Check HCLK,HDATA,FUNC signal
YES
Relay respond properly?
NO
YES
Wate for 10 second
Press listen,mode,biamp key
to change input and out put
mode
Input 2V RMS 1K sinewave,turn
volume to 0dB,measure
preoutput level and THD
Level=2V±0.1V ?
B
Check U105,U205,U104,U107,U204,U207
Check VOL_ CLK,STB,DATA(L/R) signal
Check VOLA signal and 1Q28
Check Q103,Q203,Q101,Q102,Q201,Q202
Check U101,U201,U106,U206
YES
THD>0.01%?
NO
YES
NO
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