555 board/kit

[Lance]

I was thinking about having 555 driver boards custom made and then selling them alone or in kits. Would anybody be interesting in buying them? Depending on the resistors/cap you use it can be made to do a lot of stuff. Some of the more entertaining uses would be driving a flyback or ignition coil. Obviously having them made for cost a fair bit of money so I don’t want to jump in to this if nobody has any interest.

 

So what do you think? Market or no?

[YT2095]

I think it would be great idea! I started in a similar fashion myself

 

 

go for it!

[drz]

could I use such a contraption to convert points style ignition into solid state?

 

a cheap(er) kit of this nature would be a sure sell, least round these parts.

[Lance]

could I use such a contraption to convert points style ignition into solid state?

What exactly is points style? I am unfamiliar with automobile applications.

[drz]

points is basically a mechanical switch that powers the coil, which in turn powers the spark plug. The switch is operated by (depending on the vehicle) raised areas on the distributors shaft that open the switch.

 

It is old technology, for instance, I have them on a 1976 datsun truck. Most Volkswagen Bugs have them, I'm sure several other old vehicles. Solid state is more up to times, using something like a timer circuit, set to power the coil at certain intervals.

 

Points suck for several reasons. Leave your ignition on for like, 3 seconds, points go bad. Open your distributor cap on a rainy day, points go bad. Sometimes, points just go bad.

 

I had looked into building my own ignition stuff once upon a time, but lack the time and knowledge, always burn myself with the soldering iron, etc. I know it can be done with a 555 timer, but figuring out the exact moment to "fire" would be the trick.

[Lance]

points is basically a mechanical switch that powers the coil' date=' which in turn powers the spark plug. The switch is operated by (depending on the vehicle) raised areas on the distributors shaft that open the switch.

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Oh, ok thanks.

 

Well you would not have to figure out any specific time to 'fire' because the coil would be run at a few thousand hertz for several seconds.

 

What kind of circuit drives the coil in new cars?

[Lance]

By the way heres the schematic I'll be testing

[YT2095]

put a reverse biased diode across L1, else the back emf will blow out T1.

[RICHARDBATTY]

In newish cars there are two coils. The supply is switched btween them. Each coil gives two sparks at the same time. One spark is used for ignition and the other is wasted on the exhaust cycle of another cylinder.

[drz]

hmm, I've never seen such a setup. The only dual coil vehicles I know of were 80's model Nissans, which had two spark plugs per cylinder, and a coil for each set of 4. Most modern cars I've seen use whats called a "Core Pack" which is basically a digital version of a distributor and coil.

 

I know you cannot adjust timing on newer cars with core packs, because there isn't really a distributor.