Re: Help with strange audio fault #qcx


Alan G4ZFQ
 

James wrote:
If it fails these 2 tests you have a connection problem at pin 5.
Ted,

Are your voltage readings taken when the fault is present? If so then surely pin 5 is correct? (James, Ted is using his DVM which is not loading the circuit like Hans' figures show.)
I'm concerned about pin 6 which should be connected to pin 7 by R38, as there should be no other DC connection to pin 6 it should therefore be close to the pin 7 voltage.
Is R38 soldered? Check it's value, that each end is actually connected to the IC pins. Check the resistance from pin 6 to ground.

73 Alan G4ZFQ

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