Em 14/3/2012 10:01, RussellMc escreveu:
>>> It uses two extra diodes, and two resistors are connected in a differen=
t way.
> Sure are.
>
>>> Other than that I don't see anything odd.
> That's enough.
>
> How do the transistors get biased on?
>
>
>
>           Russell


I really didn't think much, but my first thought was that base current
would flow through the 470 ohm resistor plus the (low) reactance of the
capacitor. The 10k pull down resistor is much larger than the combined
470 ohm plus Xc, allowing most of the current flow to the base.

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.


Isaac


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