> Out of coffee error

           12648430_d =3D 0 !

_____________

This is by far the more important :-).

Gain of a single transistor stage "by inspection".

Emitter resistance is dynamic and inversely proportional to emitter current=
..
Plug in th figures for Si and you get Re =3D 26.4 ohm . mA
ie at 1 mA Re ~=3D 26.4 ohm
At 2 mA Re ~=3D 13.2 mA.

BUT Ie ~~ Ic.
Vload =3D I.load . Rload. ~=3D Ie. Rload

Stage Gain bypaseed or grounded emitter =3D Rload/Re

=3D Rload / (26.4 ohm.ma)

Fiddle and

Gain =3D Vload_DC x 38
(38 =3D 1/0.0264 )

ie gain of a transistor stage can be determine by inspection !!!
Max gain < 38 x Vsupply small signal.
Gain rail - rail < ~ 19 x Vsupply !



     Russell





On 27 June 2011 02:02, Michael Watterson <mike@radioway.org> wrote:
> On 26/06/2011 14:44, RussellMc wrote:
>> Sample; =A0 =A0 =A0 =A0 =A0Max gain of a single silicon transistor ampli=
fier
>> stage =3D~ 38 x Vload_DC_drop.
>>
>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0Q: Why
>>
>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0A: =A0 =A0Re =3D 26.4 V.mA !!=
!:-).<-- V.mA =3D R but
>> missing the point:-)
>>
>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0Clue 26.4 x ~38 ~=
=3D ?
>>
>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 So eg a single transistor am=
plifier operating on
>> 5V =A0has max possible gain of about 190 small signal.
>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 For max Vout gain max ~=3D 9=
5
>>
>

>
> I'd have likely just used single Hebrew letters. They look pretty. :)
> There are 3 main forms. The modern handwriting version. "Type" version
> is too slow and ancient one not as pretty.

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