BBK DK2810HD, Service Manual

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Example 5 Symptom: sound receiving has no sound
Description: when receiving sound, connect left and right channels of amplifier, but there are no
sound output.
Analysis and troubleshooting: first turn on sound receiving, use probe of oscillograph to separately
check pin 3 and 13 of N501, and it is found that there is audio signal . Then check pin 4 of N502, and
there is no audio signal. While checking pin 10 and pin 12, there is audio signal. It is found that N502 is
uneffective, replace it and trouble is removed.
Example 6 Symptom: no MIC
Description plug MIC and speak, there is no audio output
Analysis and troubleshooting: plug MIC and speak, use probe of oscillograph separately test pin 7
of amplifier board N500, and there is signal input. When testing pin 3 and pin 13 of N505, there is also
signal. Then test pin 4 of N502, there is signal. While testing pin 206 of Mt1389, there is no signal. It is
confirmed that R519 is cut off. Replace it and trouble is removed.
Example 7 Symptom: remote control has no function
Description: when pressing remote control, there is not any function.
Analysis and troubleshooting: use probe of oscillograph to plug into pin 1 of decode board XS106.
When pressing remote control, oscillograph has no movement. It means that, remote control signal is
not reached. Check L91, and it is found that it is not cut or joint welding. Put probe tightly on pin 1 of
N102 on main board, press remote control, there is signal movement on oscillograph, which means that
receiver has no problem. Plug pin 2 of N101, press remote control and there is not signal movement on
oscillograph, observe carefully and found that R110 is rosin joint. Weld again and trouble is removed.
Example 8 Symptom Amplifier has no sound
Description: circuit outputs sound normally and there is also no sound output when switch into
sound receiving state. when player power on, turn on amplifier sound volume, amplifier output has small
noise. Analysis and troubleshooting: from the symptom, we confirm that trouble lies on common channel
around amplifier. Check SD signal of amplifier IC and it is always 0 V. AT this time, IC is in overcurrent or
overheat protection state. Use multimeter to test each voltage to earth of lead line of amplifier output
end , the voltages to earth of subwoof are 9V and 5V (normal one is about 14.5V). Take out L510 of this
channel, sound is normal. It is confirmed that it caused by defect L510, remove it and trouble is removed.
Example 9 Symptom: no OSD
Description: plug power, indication light of panel flicks normally. Then press power switch and
player starts normally, video signal output is also normally but there is no OSD.
Analysis and troubleshooting: check display screen and filament is lighten, and there is red light
indication but no function display. Use multimeter to check panel IC power supply and surrounding
voltages and they are all normal. Then check the CLK, STB and SDA signals from decode board to main
panel, which are normal. But lead feet of main panel TP6317 has no SDA signal and main panel R112 is
normal. After that, check grounding resistance value of pin 5 and 6 of main panel TP6317, which is 1.5
ohm. Replace TP6317 and trouble is removed.
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