who is making these transistors (originally NEC audio output)?

[capslock]

Just received these parts. Original manufacturer is NEC. The 2SC 2987 part bears the NEC mark. The S does not seem to be the gain group, as this can be R, Q or P.

The 2SA1227 part is puzzling me. I have never seen this logo of three tick marks in a circle. Again, there is no gain group.

Regards,

Eric

 

[JOE DIRT®]

Capslock the 2sa2987 is a npn 140v 12amp 120watt 60mhz transistor and the 2sc1227 is a pnp complimentary mate with the exact same specs........the latter is a probably a generic clone from a another manufacturer


Cheers!!The DIRT®

 

[Duo]

Joe Dirt: You do mean 2sc2987 and 2sa1227 do you? Instead of having the c and a mixed?

 

[capslock]

Yes, I now the specs, I even have the NEC data sheet in Japanese.

My question was who manufactured the A1227. My experience is that those clones are usually not full second sources. Just look at the data sheets for the Sanken 2SC2837 and the Mosspec clone by the same part number. Gain linearity, fT and Cob are so much worse that the part should not be allowed to go by the same number. I have some WEC parts for which I found no data sheets which are, judging from simple measurements, also much worse than the orginals.

 

[Netlist]

My question was who manufactured the A1227.

Capslock, have you tried this:
http://www.angelfire.com/electronic2/rch/logoa.html

Greetings
/Hugo 🙂

 

[capslock]

Hi Hugo,

thanks for the link. Unfortunately, not all letters work (dead sub-links). I will keep trying.

Greetings,

Eric

 

[JOE DIRT®]

my apologies I did mix up the the letters Duo

DIRT®

 

[Netlist]

Unfortunately, not all letters work (dead sub-links). I will keep trying.

Indeed, perform a search on "IC logo", or "IC id" or similar things.
There is more to find, however, I gave up after 15'; Ones get dizzy by looking at all those logo's
You could try this too: http://tess2.uspto.gov/bin/gate.exe?f=brwsidx&state=e7qht4.1.1
but then you're busy for months.. 😉
/Hugo 🙂

 

[thanh]

I want to view 2SA1227's datasheet . I searched it by google but it is to difficult to look for it . Who can help me ?