Gareth Magennis wrote:
"Archon" wrote in message
. ..
Gareth Magennis wrote:
"N_Cook" wrote in message
...
Gareth Magennis wrote in message
...
Hi,

can anyone identify this transistor?
Marked H
669A




Its in a To 126 size all plastic package but a fair bit thicker, one I
have
not seen before. (why?)
Its an NPN with lead out BCE. Its directly on the heatsink of a power
amp
in series with a thermistor, so is either part of the bias circuitry or
temperature sense. I don't have a schematic.



Cheers,



Gareth.


180 volt 2SD669A with reversed pinning ?
NPN and TO126 but ECB


Ah, just realised that the legend is actually on the back of the device -
it was mounted legend side to the heatsink, and on closer inspection the
pins are closest to the legend side, so it looks like you might well be
correct.


It is a peculiar package, one I haven't seen before. (This is from a
cheap Chinese no name power amplifier, so maybe this is a Chinese part?).



Thanks,



Gareth.




I think you will find Hitachi are Japanese.




Frank gets first prize, its a Chinese 2SD669A





Gareth.


Let me know when you source a Chinese one that works then, I'll stick
with Hitachi thanks. Surprised they even bothered to put numbers on it.