"Heavy Duty" Square Wave Oscillator

Right, it makes sense now (always far better to explain whats happening, rather than people having to guess).

For the pulse expander, does it have to expand further as the engine slows down?, wouldn't multiple sparks for the same time period work as well?.

BTW, what's the object of the multiple sparks? - I don't really see how it can affect performance?, but presumably it does if you're bothering doing it?.

Nigel Goodwin said:

Right, it makes sense now (always far better to explain whats happening, rather than people having to guess).

For the pulse expander, does it have to expand further as the engine slows down?, wouldn't multiple sparks for the same time period work as well?.

BTW, what's the object of the multiple sparks? - I don't really see how it can affect performance?, but presumably it does if you're bothering doing it?.

Click to expand...

The pulse duration varies. At 500 rpm, the breaker point keeps shorted for 2ms. At 5000 rpm, the breaker point keeps shorted for about 0.5 ms.
I need that the multiple sparks keep sparking for further to assure that I do not "lose" them.
If you see, at a classic ignition, the sparks only happen when the breaker point unshorts. If I keep sparking while the breaker point is shorted, my sparks maybe wouldn't get to the spark plug.

Well, the object of multiple sparks is to assure an efficient and faster combustion.
Some times, when exaust gases are analysed, there is much presence of fuel and oxygen as well.
If there is fuel and oxygen, the only reason that it didn't entered in combustion is that the spark power was not suficient.

It sounds like you are after a CDI ignition system, they have been available as kits for many, many years or have a look at this link.
**broken link removed**

Paul Obrien said:

It sounds like you are after a CDI ignition system, they have been available as kits for many, many years or have a look at this link.
**broken link removed**

Click to expand...

Thanks.
That will help me improve my design.

Use an XR2206.
With good resistors and caps, It should meet all your requirements.