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Problem with my Yamaha CR-400 stereo

So today i ran into a problem when i turned on my stereo. When i turned it on smoke came from the stereo and when i opened it i found this. I printed out the service manual but was unable to read it due to poor quality of it. I want to know what part it is that is broken.

Picture of problem.
http://imgur.com/GNtThxx



Problem with my Yamaha CR-400 stereo

Hi,
In this kind of final stage if a problem occurs it is better to measure every transistor,diode and resistor [start with finals and go back 4-5 transistors].Probably the finals are OK. Try first without removing the parts. Compare with other chanel. Use an AVO-meter on Diode scale than on R. Please do not use auto scale. Do not forget capacitors - above 1uF. Of course -power down. If need further asistance write again

karodimitrov's picture

Problem with my Yamaha CR-400 stereo

Check the same resistor in the other channel.Think it's 220 ohms.Check too transistor 611 and capacitor.
Turn "off"amplifier and check resistance between all the same points in 2 channels.And fix problem.(sorry for my bad english)Hope you understand me.:)

Problem with my Yamaha CR-400 stereo

That is a resistor that burned open. It looks like it is connected to Tr611, which may also be bad and also the blue capacitor. Tr611 appears to be a driver transistor, so you must assume that the output transistors are bad in that channel.

Problem with my Yamaha CR-400 stereo

what kind of a resistor is that and where can i find that resistor so i can replace it?

Thanks

Problem with my Yamaha CR-400 stereo

Just replacing the resistor will not fix the problem; it appears that Tr611 is bad and probably other parts also.