01-28-2015, 11:57 AM
While waiting for trim pot order to arrive I was checking around on the chassis looking for anythig I might have missed. I have AM but no FM. With power on I discovered that the control amp board W15-079 caps C3 & C5 and transistor Q1-2sc871 when touched or tapped make a hum and scratching sound out of the speaker. This is with unit in FM mode.
I'm going to recap this board and replace the transistors.
Heres the question. There are 2-2sc871 and 2-2sc870 transistors on the board.
The searches for replacements show use KSC1845 for all four transistors,but 2 of them are pnp.( the 871s) according to schematic and KSC1845s are npn.
[Image: http://i1336.photobucket.com/albums/o654...cd640d.jpg]
Here is schem. What should I use for the pnps? Or am I misreading schem.?
Thanks.
I'm going to recap this board and replace the transistors.
Heres the question. There are 2-2sc871 and 2-2sc870 transistors on the board.
The searches for replacements show use KSC1845 for all four transistors,but 2 of them are pnp.( the 871s) according to schematic and KSC1845s are npn.
[Image: http://i1336.photobucket.com/albums/o654...cd640d.jpg]
Here is schem. What should I use for the pnps? Or am I misreading schem.?
Thanks.
