Nigel Goodwin said:
To be honest, your entire scheme makes no sense at all? - and why would you want 50% duty cycle to feed an ignition coil? - essentially the coil charges up while the points are closed, and generates the spark (by it's back EMF) when the points open.
I think we are being off topic here.
We are discussing if it will work or not, let this subject to me!
But it's my fault, because I'm not making myself too clear.
I'll try to clarify.
The main purpose of 50% duty cycle is to have
multiple sparks while the breaker point is shorted.
For example, in a traditional ignition system, I'll have 1 pulse (driven by the breaker point), consequently I'll have 1 spark.
If I use the breaker point to drive a circuit, to deliver several pulses, consequently I'll have several sparks.
I made a drawing:
**broken link removed**
There is why I need a "pulse expander" too.
If the Breaker Point keeps 2ms shorted, I need a "pulse expander" to make the oscilator oscillate for 6ms period.
If the Breaker Point keeps 3ms shorted, I need a "pulse expander" to make the oscilator oscillate for 9ms period.
And so on...