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

capslock · 11th August 2003, 06:43 PM

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® · 11th August 2003, 07:36 PM

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 · 11th August 2003, 08:37 PM

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

capslock · 12th August 2003, 08:47 AM

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 · 12th August 2003, 10:04 AM

Quote:

Originally posted by capslock
My question was who manufactured the A1227.

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

Greetings
/Hugo

capslock · 12th August 2003, 11:45 AM

Hi Hugo,

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

Greetings,

Eric

JOE DIRT® · 12th August 2003, 11:50 AM

my apologies I did mix up the the letters Duo

DIRT®

Netlist · 12th August 2003, 02:54 PM

Quote:

Originally posted by capslock
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?...ate=e7qht4.1.1
but then you're busy for months..

/Hugo

thanh · 15th July 2005, 06:19 AM

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 ?

11th August 2003, 08:37 PM	#3
Duo diyAudio Member Join Date: Jun 2002 Location: Victoria, BC, Canada	Joe Dirt: You do mean 2sc2987 and 2sa1227 do you? Instead of having the c and a mixed? __________________ -- Duo, W1ngs, VA7MON, and lesser known handles. -- -- http://www.w1ngselectronics.com -- My Work and Projects --

15th July 2005, 06:19 AM	#9
thanh diyAudio Member Join Date: Jan 2004 Location: ho chi minh city	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 ? __________________ Justice for Victims of Agent Orange http://www.petitiononline.com/AOVN/Thank all of you!

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11th August 2003, 07:36 PM	#2
JOE DIRT® diyAudio Member Join Date: Apr 2003 Location: Brantford, ON	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®

12th August 2003, 08:47 AM	#4
capslock diyAudio Member Join Date: Feb 2002 Location: Germany	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.

12th August 2003, 11:45 AM	#6
capslock diyAudio Member Join Date: Feb 2002 Location: Germany	Hi Hugo, thanks for the link. Unfortunately, not all letters work (dead sub-links). I will keep trying. Greetings, Eric

12th August 2003, 11:50 AM	#7
JOE DIRT® diyAudio Member Join Date: Apr 2003 Location: Brantford, ON	my apologies I did mix up the the letters Duo DIRT®