Symptom: after power on power light is on, remote control doesn't work, press the control. No sound from the left and right channels.eUbservice manual download site
Troubleshooting: power measuring power supply, after the level of operating voltages plus or minus 40 volts normal,eUbservice manual download site
eUbservice manual download site
Preamp voltage is 5 volts, 12 volt positive and negative, are normal, good filter. From the amplifier input connect the audio signal level, the left and right channels are normal sound. Measure the input audio signal into the input relay without output, measuring relays operating voltage: no, because wave relay is used as the input switcheUbservice manual download site
eUbservice manual download site
Not working can not hear the voice. Shows fault control circuit is not working properly. Remove the voltage observed, find Panel is provided by 7905 and 7805 level plus or minus 5 volts, 7805 pins have been badly welded after welding and measuring voltage, select the button enter the relay sucks and shuts, the whole sound back to normal.eUbservice manual download site