Re: 555 timer driver for ignition coil

["Ed Phillips" <evp-at-pacbell-dot-net> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Tesla list wrote:
> 
> Original poster: "B Marshall" <bm-at-bens-stuff.fsnet.co.uk>
> 
> I've also messed about with a similar circuit, which used a couple of
> transistors as an osc to
> pulse a 2n3055. This was used to drive an ignition coil. I had no problems
> with it, until I
> connected it up to a variac and put about 15v in (not sure of current, but
> the spark would ignite
> paper) which blew the 3055.
> 
> Regards,
> Ben


	The 2N3055 is a lousy transistor for this form of a coil driver, due to
the low collector-emitter breakdown voltage.  I would use a transistor
rated at at least 600 volts or more as the power switch.

Ed