On Sun, 06 Jun 2004 17:59:00 -0500, Ed Bailen wrote:

The last issue of QST had a short article on the CircuitMaker Student
edition circuit design package. I downloaded it and spent several
hours trying various oscillator designs (including the phase shift
oscillator discussed in the same issue of QST). I couldn't get any of
the designs to oscillate! I was mainly trying Colpitts oscillators.

Has anyone else tried designing oscillatos with this application?

Ed, I don't have any experience of CircuitMaker but I do have trouble with
getting oscillators to oscillate on other simulation packages. This is
inherent in the design of the simulators in that they will deliberately try
to stabilise the circuit and stop the oscillation from taking off!

If you have an option in there to 'skip initial transient solution' or
something similar, it's good to check the box and bypass it - this is the
thing that tries to DC stabilise the circuit. From there, it relies on
noise to get the oscillator start and if there isn't any, it won't...

--
Duncan Munro M0KGK
http://amateur.duncanamps.com/
BOF #023 FISTS #10815