On 30/12/2014 11:28, Mark Zacharias wrote:
"Tim Schwartz" wrote in message
...
Hello all,

Just a warning that I was about to use a "2N5401" that is marked as
follows:

2N
5401
CH13

and on the back, molded in a circle on the rear is K1 or K7 - the ones
with the K7 have the lettering slightly rotated.

On these devices, the middle pin is the COLLECTOR not the Base, as a
genuine 2N5401 would be. These devices are on a paper tape strip of
20 I bought, and unfortunately I did not keep them in the original
package, so I don't recall where they came from.

Just thought I'd mention it here, as it could cause a lot of grief
when repairing something. I did not bother to curve trace these to
see if they otherwise meet spec, as I plan to trash them. I've since
ordered some proper 2N5401's from Digikey.

Regards, and Happy New Year
Tim Schwartz
Bristol Electronics



Tim,

The 2N5401's used by Yamaha on most models the past six or more years,
are not fake and are based E-C-B like the Japanese signal transistors.
Don't know why, and I don't know why they used American designation. I
mentioned it to our tech rep and he kinda snickered.

But they aren't fake. For example, Q1071 shown on page 125 of the
RX-V773 service manual, is a "2N5401C" . I picked this manual almost at
random, but many Yamaha models use these.

Q1069 and Q1070 are '2N5551C" same ECB basing.


Mark Z.

So for more general application, not just 2N5401.
From the OP device marked
2N
5401
CH13
so could the suffix be C and then perhaps H fortnight of year 2013 as a
datecode?
and a genuine 2N5401C , C designating the pinning varient?