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Old 5th July 2009, 05:57 PM   #11
CBS240 is offline CBS240  United States
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Quote:
neither of my NEC datasheets for the a992 & c1845 refer to the other as the complement.
Hi

Fairchild makes similar devices except they name it with a K instead of a 2. They do this with all their typical transistors. Anyway, they list them as complements in the datasheet
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Old 6th July 2009, 04:41 AM   #12
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Quote:
Originally posted by Terry Demol


No worries.

If I may ask, why do you need such high beta?
Nice, high input impedence, low base currents, low offsets.

Quote:
Originally posted by CBS240


Hi

Fairchild makes similar devices except they name it with a K instead of a 2. They do this with all their typical transistors. Anyway, they list them as complements in the datasheet
The original '2S' numbers were properly assigned to the Japanese manufacturers by the JIS (Japanese Industrial Standard) council. Fairchild chose to label them as 'KS' to distinguish them as replacement parts with similar specs without stepping on the JIS system.
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Old 6th July 2009, 04:44 AM   #13
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Quote:
Originally posted by mlloyd1
is the 2SA872A series still available? i haven't bought any in a while. they might be useful here.

mlloyd1
Hitachi shows them as a current product, and B&D carries them. Good typical gains, but not as good as the Zetex ZTX795A or Toshiba 2SA970BL.
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Old 6th July 2009, 11:52 AM   #14
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Cant help with pnp parts yet but if you looking for npn s try 2sc3495, these parts are excellent.

From a newly recieved batch of 1000 trannies only 23 were below 1000 hfe.
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Old 6th July 2009, 11:57 AM   #15
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Quote:
Originally posted by StevenOH
Andrew,
2SA992-2SC1845
2SC3068 was developed without a compliment.
Wrong, here you go, 2sa1240 been using them for more than 15 years.
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Old 6th July 2009, 02:27 PM   #16
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Quote:
Originally posted by EchoWars
5. Being in current production would be nice, but otherwise reasonably easy to find.

Any devices I'm missing?
Glenn,

how about the Mitsu/Pana A979H and C2259H duals with a Beta of 600-1200.
As if you've never had Pioneer or Marantz items on your bench.
Obsolete, but still easy to find and surprisingly cheap.

(for 50V : Panasonic A798G )
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Old 6th July 2009, 03:27 PM   #17
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Quote:
Originally posted by homemodder


Wrong, here you go, 2sa1240 been using them for more than 15 years.
Perhaps you typed that number in wrong? The 2SA1240 is s dual part in an oddball six-pin package.
Quote:
Originally posted by jacco vermeulen


Glenn,

how about the Mitsu/Pana A979H and C2259H duals with a Beta of 600-1200.
As if you've never had Pioneer or Marantz items on your bench.
Obsolete, but still easy to find and surprisingly cheap.

(for 50V : Panasonic A798G )
The A979 is one I've been looking to find in quantity for a reasonable price ($1 or so). I can get pieces here and there for prices between $3.50 and $10 each, but I'm looking for something like 100 of them, and not interested in shelling out stupid prices for them. Glad I don't need them too often.

I have a bunch of the A798 F & G, and they work very well when I can use them.
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Old 28th August 2013, 09:07 PM   #18
balerit is offline balerit  South Africa
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I'm looking for TO92 NPN transistors to replace LM394H, gain 550 @ 10 uA, any ideas, preferably with ECB config?
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Old 29th August 2013, 08:27 PM   #19
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bc547c/bc557c ?
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Old 29th August 2013, 11:45 PM   #20
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I don't think so. LM394 is a multiple transistor, with many parallel transistors formed on the one substrate to achieve otherwise impossible matching by virtue of averaging the individual junction properties.

You won't get anywhere near that match quality or low drift without extremely precise matching of duals, also on the same substrate. Then again, if you don't really need the "supermatch" properties, you may find these useful, if also obsolete: http://www.analog.com/static/importe...ts/SSM2210.pdf
http://www.analog.com/static/importe...eets/MAT02.pdf

You can still obtain LM394H if necessary - there are a few realistic opportunities on the net with a little help from Google. However, this recently revised doc. by TI suggests some renewed manufacturing interest: http://www.ti.com/lit/an/snoa626b/snoa626b.pdf
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Last edited by Ian Finch; 29th August 2013 at 11:48 PM.
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