Yamaha CR-820 - smoke from "fuse resistor" in left channel

[wishmasterX]

Hi, Everybody ...

Is there anybody, who can help me with this problem ?
I have this receiver from my friend ... One of the fuse 1.6A was burned ...

I checked the output transistors: Right channel have original transistors / I Compared with service manual /, but left channel had :
Toshiba 2SD551 and NJM150004G ... I checked them on multi-tester and one "he looked" as double resistor and the second as double diode ...
I install new pair of NJM15003G+NJM15004G and new fuse, I turned on the receiver, the relay clicks, but the fuse resistor starts to smoke after a while ...
by the way, the original fuse resistor was previously replaced by two classic resistors in series, I estimate them at 0.6W ...

I don't know, what can I do next, I am aware that the new transistors what I used are not listed as suitable replacements, but the receiver worked with them before ...

Thank´s for any help ! Martin.

 

[jeromach]

There is another issue somewhere, you need to check surrounding transistors, diodes and resistors + check on solder issues.

Using a dbt wouldn't do any harm either...

 

[cademan]

Sounds like a shorted transistor somewhere. What is your level of expertise?

What is the unit in particular you are working on?

Might want to look up the original transistors and see if they are still available. Plus, usually when one transistor shorts, it will take another one with it. The emitter resistors associated with that bad transistor will also need to checked.

 

[avionic]

Welcome aboard Martin..

Hi, Everybody ...

Is there anybody, who can help me with this problem ?
I have this receiver from my friend ... One of the fuse 1.6A was burned ...

I checked the output transistors: Right channel have original transistors / I Compared with service manual /, but left channel had :
Toshiba 2SD551 and NJM150004G ... I checked them on multi-tester and one "he looked" as double resistor and the second as double diode ...

I install new pair of NJM15003G+NJM15004G and new fuse, I turned on the receiver, the relay clicks, but the fuse resistor starts to smoke after a while ...
by the way, the original fuse resistor was previously replaced by two classic resistors in series, I estimate them at 0.6W ...

I don't know, what can I do next, I am aware that the new transistors what I used are not listed as suitable replacements, but the receiver worked with them before ...

Thank´s for any help ! Martin.

Thats kinda vague..

the original fuse resistor was previously replaced by two classic resistors in series, I estimate them at 0.6W ..

Either post a good clear photo or give me a correct FR or R # of that fusible resistor your refering to. example FR123 or R123