> > > How do the transistors get biased on?Given asymmetries in the values =
of
> components and in the gain of the
> > transistors, one transistor would conduct first and keep the other's
> > base starved from current, until the capacitor to the base of the first
> > transistor charges and its base current stops.
> >
> > Just perhaps it could work with careful choice of components values.
>=20
> Or careless ;-).
>=20
> For either base to get to say 0.5V there needs to be 50uA leakage
> through the caps.
> (9V - 2V LED) =3D 7V.
> 7V divided 6.5V/ 0.5V. Cap/Resistor.
> I =3D V/R =3D 0.5/10k =3D 50 uA.
>=20
> Good quality 85 C std caps tend not to work.
> Junk may.
>=20

It's not leakage. Just how a capacitor works. When current goes into one le=
g it=20
goes out of the other. When it does the voltage over the dielectric also ri=
ses=20
more and more until it prohibits any more current flowing (causing the=20
capacitor charge/discharge curve). No electrons are actually moved from one=
=20
side to the other though (electrostatic repelling forces of charges of equa=
l=20
polarity).

You can compare a capacitor in an electric circuit with a barrel with a=20
flexible water tight membrane in the center (dividing the barrel in two par=
ts)=20
in a water flowing circuit. When water pushes in on one side, the membrane=
=20
flexes at the same time as water is pushed out on the other side. The membr=
ane=20
flexes as much as the water pressure allows. To high pressure and the membr=
ane=20
breakes causing a short. It is also the membrane that holds the energy in t=
he=20
barrel, allowing it to push back water when the pressure is lowered. Also, =
the=20
more flexed the membrane is, the more work is needed to flex it even more.

At least, that's how I picture the inner workings of a capacitor.=20

=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
Ruben J=F6nsson
AB Liros Electronic
Box 9124
200 39 Malm=F6 Sweden
www.liros.se
Tel +46 40142078
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D

--=20
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