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From: Reinhard Zwirner on 4 Dec 2009 12:20
Hello,

I'm asking for help with identification of three sm devices.

1. Q1, marked "I GE": probably N-channel JFET
_
2. D2, marked "A 7": diode or BJT used as a diode
<http://www.bilder-hochladen.net/files/12b4-4w-jpg.html>

_
3. Q2, marked "M 5": probably PNP BJT
<http://www.bilder-hochladen.net/files/12b4-4x-jpg.html>

BTW, the photos show the PCB of Sony's AN-102 active antenna.
Q1 works as RF amp, D2 (and not shown D1) are used for input
protection.

Q2 is the electronic switch which connects the RF amp stage to
the supply voltage.

TIA

Reinhard
From: Raveninghorde on 4 Dec 2009 15:28
On Fri, 04 Dec 2009 18:20:05 +0100, Reinhard Zwirner
<reinhard_zwirner(a)web.de> wrote:

>Hello,
>
>I'm asking for help with identification of three sm devices.
>
>1. Q1, marked "I GE": probably N-channel JFET
> _
>2. D2, marked "A 7": diode or BJT used as a diode
><http://www.bilder-hochladen.net/files/12b4-4w-jpg.html>
>
> _
>3. Q2, marked "M 5": probably PNP BJT
><http://www.bilder-hochladen.net/files/12b4-4x-jpg.html>
>
>BTW, the photos show the PCB of Sony's AN-102 active antenna.
>Q1 works as RF amp, D2 (and not shown D1) are used for input
>protection.
>
>Q2 is the electronic switch which connects the RF amp stage to
>the supply voltage.
>
>TIA
>
>Reinhard

What is wrong with google? I typed in smd markings and my favourite
is 3rd

http://www.marsport.org.uk/smd/mainframe.htm

A7 = BAV99
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