> It simply won't work with R3 and R4 base resistors grounded rather than c=
onnected to
> Vcc, since there is nothing to bias the transistors on when it's powered =
up.
>=20

Not true, if the publisher of the circuit had a pair of 100uF caps that wer=
e at the end limits of tolerance in value this circuit would power up quite=
 happily, as the charge current through the caps will turn the transistors =
on. With differences in cap values one transistor will get more base curren=
t than the other once the cap charging current is >60uA (to get 0.6V across=
 10k).

Any astable multivibrator relies on some component imbalance to start oscil=
lating, as exactly balanced components will result in both transistors draw=
ing equal current at the same time, to a point where the collector voltage =
on both transistors rises exactly equal, and eventually the caps will be ex=
actly equally charged.
--=20
Scanned by iCritical.

--=20
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