Re: Inductive Kick Effects

At 10:28 AM 6/19/99 -0400, you wrote:

>I never considered this either, but it certainly makes sense.  It looks
>like we have to be more concerned about the LTR arrangements overvolting
>things, than the reso-caps.  I noticed that my sync gap is firing about
>60 degrees past the peak.  I haven't yet done a comparison to see
>what firing position gives the strongest inductive kick voltage rise,
>maybe the simulations show this?  In my system, when the voltage
>dips lower just after firing, it reaches a level that is about 1/4 the 
>(absolute value) level that is ultimately reached at the opposite 
>polarity.  I suppose this effect might occur at 240bps or higher also,
>to some degree?  More below.

In my case, my coil likes to fire 29 degrees late.  However, this depends a
lot on the particulars of a given system.


>Can static gaps be set to such a spacing that this effect will occur?
>This might explain why Gary got good results with static gaps and
>LTR's, and I generally didn't.  I'll have to look at that again.

Very possibly!  I thought that LTR systems needed nice controlled sync gaps
to give the needed late firing times but with this new inductive kick
thing....  It is also very possible that the resistors we use in the
protection filters (RC) for these systems (Gary and I use the same scheme)
are very important for this "kick" effect...  

>Thanks guys, definitely an interesting development.
>John Freau

Thank YOU John for discovering this important effect.  We would have never
figured it out if not for you seeing "some strange results"!  Glad you
weren't going insane! :-))