djmtascam
Active Member
Hoping someone can help me out with this....
I've been looking into finding the problem with a 2amp fuse blowing on one side of the receiver's amp channel board.
I found one 1/2ohm 2W resistor with a broken lead and the white casing crumbled when I went to measure it and lift it out.
The output transistor connected to that resistor shows a shorted C-E (#2A).
I removed the other 3 output transistors to check them and it looks like the rest of them are OK per my table below?
Do I need to get a matched pair for that channel and replace both?
2SC793
+ - 1A 1B 2A 2B
B - E .325 .521 .395 .512
E - B OL OL OL OL
B - C .457 .526 .393 .488
C - B OL OL OL OL
E - C OL OL Short OL
C - E OL OL Short OL
I found NTE130 or NTE130MP replacements available at Mouser.
$4 for one or $9 for a matched pair....is this a good deal?
And I need to find a new resistor...
Is there any reason to replace all of output transistors and recap the amp board?
I'm fixing this for my buddy as part of his Xmas present, so I'm hoping I can get it all done by then....
Any suggestions or comments would be greatly appreciated!
I've been looking into finding the problem with a 2amp fuse blowing on one side of the receiver's amp channel board.
I found one 1/2ohm 2W resistor with a broken lead and the white casing crumbled when I went to measure it and lift it out.
The output transistor connected to that resistor shows a shorted C-E (#2A).
I removed the other 3 output transistors to check them and it looks like the rest of them are OK per my table below?
Do I need to get a matched pair for that channel and replace both?
2SC793
+ - 1A 1B 2A 2B
B - E .325 .521 .395 .512
E - B OL OL OL OL
B - C .457 .526 .393 .488
C - B OL OL OL OL
E - C OL OL Short OL
C - E OL OL Short OL
I found NTE130 or NTE130MP replacements available at Mouser.
$4 for one or $9 for a matched pair....is this a good deal?
And I need to find a new resistor...
Is there any reason to replace all of output transistors and recap the amp board?
I'm fixing this for my buddy as part of his Xmas present, so I'm hoping I can get it all done by then....
Any suggestions or comments would be greatly appreciated!