Herbert Graf wrote:
> If this is a distributerless ignition we are talking about then a hard
> clamp of one diode drop would not be what you want,

I haven't really been following this that closely, but a diode to catch
kickback from the primary of an ignition coil would cause a diode drop plus
12V, not just a diode drop.  Again, maybe a different topology was discussed
than what I'm thinking about.

An ignition coil is essentially a pulse transformer with a very high output
ratio.  You want to let the primary go as high as you can tolerate to force
most of the energy out the secondary.  It seems to me that a simple diode to
+12V in series with a resistor would be adequate.  The maximum possible
current in the primary is easily known, so the resistor can be sized so that
the primary voltage is just below the tolerable limit at maximum current.
The voltage will be less in all other cases.


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