Hello all! My son got my older kenwood amp the other day and ran speaker wires wrong causing the amp to blow fuses! I replaced fuses with fast acting and they would just blow! A friend said I needed slow blow fuses because of the amound of current at start up! I tried the slow blow fuse and it didnt blow them this time! Well I have lights now but no sound! Also its not heating up like it use to! I know a little about electronics, but this has me stumped, because I open the case and there is no sign of burnt op amps or blown caps! Im thinking it could be shorted filter cap, but was just wondering if anyone tell me where a good place to start checking would be? Thanks
The output transistors have most
likely failed on that amp.
the correct replacement transistors are
DAT1521P X 4
DAT1521N X 4
Thats the full complement, you need to identify
which channel was shorted and replace the four
drivers that correspond to that channel.
There will also possibly be burnt out 22ohm
resistors on the underside of the small circuit
board of the blown driver/transistor.
It is fixable and the parts are available.
Hope this helps, it would be a shame to let that
Basic M2 go.
HI!
I believe I'm having the same problem..I have located the transistors, and both boards have been separated from their respective transistors by what looks to be melting (2 of 4 boards, 4 of 8 transistors). There is a little circular brown thing (maybe resistor) that needs to be replaced as well (there are a few numbers and letters on it -- E/103P). Is this possible to fix myself with the right parts?
In love with this amp. ANY comments are greatly appreciated.
That brown component is a 10nf (nanofarad) ceramic capacitor, if you replace
one then you should replace all of them, I think there are two, one for each high power stage.
The solder may have melted from heat generated when the transistors failed.
You should probably replace the low power pre drivers for each pair of power
transistors that failed.
These low power devices are located on the main board below and to the right
of the main high power driver transistors, there part numbers and quantity required are below.
2SA1006 times 2
2SA939 times 2 (no longer available use BF472 )
2SC2071 times 2 (no longer available use 2SC2371 )
2SC2336 times 2
Check the 22ohm quarter watt resistors on each of those four small pc boards
and replace if they look even slightly darkened, better still just replace them.
Of course this is all based on the assumption that you
have blown output transistors.
Remember to disconnect the power completely before you
start poking around inside the case.
Hello!
I recently got an Kenwood Basic M2 from a friend.
Unfortunately the amp is blown. Affected are the lower 2 transistors with their boards as well as the area below them (if you see it so the fan is on the right).
My problem is I don't know which parts were there (completyly burned/exploded).
It would be great if someone could post a close-up picture for me and/or give me the name of some alternative parts that can be used instead of the 2 big transistors (they are special japanese types, I think).
Thanks.