On Mon, 7 Jun 2004 17:21:03 -0500, "Steve Nosko"
wrote:

Out of the box on PSpice I got both a 555 and Colpitts to fly.

The 555 should start unconditionally, since it is based of the RC time
constant and two comparator levels. Thus, it should not matter, what
the initial charge in C is, since sooner or later one of the
comparators will change state.

A startup transient in the Colpitts may very well start the
oscillation, since the transient is rich of harmonics and if one of
the harmonics is connected back with sufficient gain through the
frequency selective feedback, the oscillation should start.

Paul OH3LWR