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Lg BH7440P s protection

Lazarous3rd

Feb 21, 2021
2
Joined
Feb 21, 2021
Messages
2
Hello all, I'm a newbie to electronics so please be gentle lol
I have an LG home theater system mentioned above and suddenly the sound had gone on it and it goes in to s protection mode. I have opened the case up took the amp board out and looked for obvious damages or burns but couldn't see anything visual so I have started measuring all the components. I have realised there are 4 3pin transistors on there under q701,q7012 and so on. I have measured them with multimeter for continuity and have realised all of them are in the range of 600-700 apart from one which hovering over a 1k. I have read it in some forums that that means a transistor is gone. I have been trying to buy a transistor since but couldn't get my hands on one where the transistor measures exactly the same way on the pins as the one on the amp board. Would any one buy any chance would know what transistor would I need here?
I would appreciate any help.
Thank you
 

Martaine2005

May 12, 2015
4,951
Joined
May 12, 2015
Messages
4,951
You will need to read the part number on each transistor. Look carefully and you’ll see it.
You can’t always measure components in circuit as others around it can influence the measurement. Also whether it’s NPN or PNP, so you really need to find that out. There are plenty of online videos showing how to check transistors.

Martin
 

Lazarous3rd

Feb 21, 2021
2
Joined
Feb 21, 2021
Messages
2
Thanks for the advice Martin, I will have a look tomorrow and see if I can locate the transistor that way.
Laszlo
 
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