On Wed, 6 Nov 2002, Roman Black wrote:

*>Peter's suggestion of putting the cap C-B is bad
*>as when the relay rutns off the collector goes to
*>PSU+1v, the cap couples this sudden rise directly
*>back to the base and it makes a good oscillator.
*>B-E makes it oscillate less, C-B makes it oscillate
*>more. :o)

Please please please build that circuit before posting more like this. For
any oscillations to take place in that circuit the capacitor should have
at least 90 degrees of phase shift in it at the preferred resonant
frequency and the necessary gain would require a superbeta transistor and
a relay with a loaded coil Q in the hundreds. Which is impossible by
definition (the collector current of the transistor is loading it down).

Peter

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