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Difficulty identifying SMD semis via markings

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DaveC

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May 27, 2010, 3:24:36 PM5/27/10
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I've never had to look up a SMD semi before now. Unlike JEDEC codes, these
less-than-brief alphanumeric codes have no standard that I can find.

And if there's no manufacturer mark (or it has become illegible), there's no
hope of finding a replacement.

In my case:
HFJ (the "J" is smaller than the others), 3 terminal, SOT-23 size.

I'm speaking, of course, of a circuit that has no schematic available for it.


Is there a device code data base? Maybe I just missed it in my Yahooing?

Thanks.

Meat Plow

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May 27, 2010, 3:36:58 PM5/27/10
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http://www.marsport.org.uk/smd/

DaveC

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May 27, 2010, 11:35:25 PM5/27/10
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> http://www.marsport.org.uk/smd/

No "HFJ" listings.

Thanks,
Dave

Franc Zabkar

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May 28, 2010, 2:46:40 AM5/28/10
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On Thu, 27 May 2010 12:24:36 -0700, DaveC <inv...@invalid.net> put
finger to keyboard and composed:

FWIW, a "HF" marking code identifies a Toshiba 2SC3124 NPN transistor,
15V, 50mA, for TV Tuner, VHF Oscillator Applications:

http://www.datasheetcatalog.org/datasheet/toshiba/1264.pdf

The lowercase "j" may be unrelated to the part number.

For example, a Philips BCW89 transistor has a marking code of H3*,
where *=p for "Made in Hong Kong", or *=t for "Made in Malaysia".

http://www.nxp.com/documents/data_sheet/BCW89.pdf

You may be able to discern the manufacturer, or country of origin,
from the surrounding components. The function of the device may be
deduced from the circuit itself. For example, is the board part of a
tuner?

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.

Message has been deleted

Meat Plow

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May 28, 2010, 9:13:36 AM5/28/10
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Sorry, was the only URL I had.

Uffe B�rentsen

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May 28, 2010, 2:46:00 PM5/28/10
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"DaveC" <inv...@invalid.net> skrev i en meddelelse
news:0001HW.C8241504...@news.eternal-september.org...

There is a database here:
http://www.clivetec.0catch.com/SMD_Codes.htm


and here you can find HF:
http://www.clivetec.0catch.com/SMD_CodesH.htm

--
Uffe B�rentsen


Rich Webb

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May 28, 2010, 3:01:51 PM5/28/10
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Warning ... Do not visit the above site with javascript enabled and/or
an industrial strength pop-up blocker if you value your sanity (and
possibly your PC).

--
Rich Webb Norfolk, VA

Meat Plow

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May 28, 2010, 3:06:27 PM5/28/10
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On Fri, 28 May 2010 15:01:51 -0400, Rich Webb wrote:

> On Fri, 28 May 2010 20:46:00 +0200, "Uffe Bærentsen"

Chromium for Linux seemed to handle the pop-up crap well. Clivetech needs
to find a better free host.

DaveC

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May 28, 2010, 3:34:53 PM5/28/10
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> Warning ... Do not visit the above site with javascript enabled and/or
> an industrial strength pop-up blocker if you value your sanity (and
> possibly your PC).

Yeah, I saw that. Pretty intense pop-ups. Still, the data is worth the trip.

Dave

DaveC

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May 28, 2010, 3:34:58 PM5/28/10
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> There is a database here:
> http://www.clivetec.0catch.com/SMD_Codes.htm
>
>
> and here you can find HF:
> http://www.clivetec.0catch.com/SMD_CodesH.htm

Thanks, Uffe!

Dave

DaveC

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May 28, 2010, 3:35:16 PM5/28/10
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> FWIW, a "HF" marking code identifies a Toshiba 2SC3124 NPN transistor,
> 15V, 50mA, for TV Tuner, VHF Oscillator Applications:
>
> http://www.datasheetcatalog.org/datasheet/toshiba/1264.pdf

Thanks.

> The lowercase "j" may be unrelated to the part number.

Not lowercase. Uppercase, just smaller type than "HF"

> For example, a Philips BCW89 transistor has a marking code of H3*,
> where *=p for "Made in Hong Kong", or *=t for "Made in Malaysia".
>
> http://www.nxp.com/documents/data_sheet/BCW89.pdf
>
> You may be able to discern the manufacturer, or country of origin,
> from the surrounding components. The function of the device may be
> deduced from the circuit itself. For example, is the board part of a
> tuner?

Acquisition PCB, Tek TDS420 scope. No schematics in the public domain.

Thanks again,
Dave

Message has been deleted

Uffe B�rentsen

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May 29, 2010, 7:44:54 AM5/29/10
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"DaveC" <inv...@invalid.net> skrev i en meddelelse
news:0001HW.C82568ED...@news.eternal-september.org...

Sorry for that.
My TrendMicro took care of all that for me.

--
Uffe B�rentsen


Rich Webb

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May 29, 2010, 8:44:28 AM5/29/10
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Can't blame them for trying to raise revenue, I guess. One would think,
though, that they'd turn it down a notch or two so as not to chase
people away. Or at least have dancing bears and cute puppies! ;-)

JosephKK

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Jun 8, 2010, 4:39:04 AM6/8/10
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On Fri, 28 May 2010 15:01:51 -0400, Rich Webb
<bbe...@mapson.nozirev.ten> wrote:

>On Fri, 28 May 2010 20:46:00 +0200, "Uffe Bærentsen"

No-script in Firefox seems to have stopped the hosting driven crap cold.

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