A new ignition circuit

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Hi John
I watched your video and was able to capture the big spark in a still pic.
I'm in the process off putting it together today .
Thanks again for all the help and sharing.
John VK.
 
Hi John VK,

Can you post that picture? How did you make out with your circuit build?

Cheers!
John
 
Hy guys.
I've never posted anything yet as I'm pretty new to this stuff.
Here are the frames I was able to capture off John's video.
The pic's are no hell but they do show a very good spark.
I've asembled the circuit but hv'nt tested it yet.
I had a little trouble finding out the output pins of the alegro HED but found the data sheet for the device today
will test run tomorrow.
JohnVK

PICT0030.jpg


PICT0033.jpg


PICT0035.jpg


PICT0036.jpg
 
Hi,
I was just wondering if anyone had yet actually used this in a working model and is so what your experiences/results were?

Terry
 
Hi,
I was just wondering if anyone had yet actually used this in a working model and is so what your experiences/results were?

Terry


Hi Terry:

The circuit works well. John and I worked together on this design. It's essentially a little more elegant and durable version of what I've been using for quite some time with good success. As with any ignition it comes down to the coil you have to throw at it. But it should be able to drive anything including a full sized car coil. (with a ballast resistor). See the connection diagrams posted a ways back.




Dave Sage
 
Have any of you thought of adding a charging system so that you could run without batteries?

Choefer:

Without a battery - How would you start it in the first place?
I can imagine one could easily create a generator to charge the battery if that's what you mean.

Sage
 
Choefer:

Without a battery - How would you start it in the first place?
I can imagine one could easily create a generator to charge the battery if that's what you mean.

Sage

If your drill spin it fast enough your charging system
(small dc motor) should give you enough voltage power
to ignite the circuit, but will you have enough current
to get your coil to work:hDe:
 
Just FYI for those of you looking for a cheap place in the US or Canada for PCB's. I've been using Alberta Printed Circuits (www.apcircuits.com) for years. Usually a few days normal delivery for boards and cheap, cheap, cheap. I paid $50 for 4 pcs of a small, double sided (1x2") board with plated through holes, solder mask and silkscreen.
 
Choefer:

Without a battery - How would you start it in the first place?
I can imagine one could easily create a generator to charge the battery if that's what you mean.

Sage

I have several normal small engines that run and start without batteries. though i am new to the 'model' engine universe i am not new to small engines. some machines that have engines that run in this manner are: weedeaters, generators, push-mowers, snow-blowers, rototillers, small outboard boat engines, etc. while many of these are run with magnetos, some run with small generators. one example of which is a 1970s Mercury outboard engine with thunderbolt ignition. similar to a magneto, it uses small stator coils and magnets under the flywheel to create a voltage, but with the generator the voltages are lower (200-300V) and that power is then fed to the main ignition coil and control circuit. in fact it is kinda cool how they work. Often there are more than one type of stator coils that function at different rpms, allowing the spark to be strong no matter. i just thought it would be a fairly simple step to take the battery out of the loop so that you no longer have to worry so much about current draw or going to a show without good batteries.

Casey
 
I have some questions about the grounds for this board. I'm sorry but I can't read electrical schematics.

I do know what the ground symbol is though.

1. Where does the ground go for at line E3 that runs off C3.
2 " " " " " " " " E5. I'm assuming this is batt neg post.
3 " " " " " " " " E7.
4 " " " " " " " " E8 off of D3.
5 And finally where does the ground go at E4 off of Q1 where it says "see note 5"


I'm sorry if this seems obvious to most people but I'm not learned in electronics. My son can read the plan and build the board but he doesn't know ignition systems so he doesn't know where they go either.

Thanks

Ron
 
The diagram is at post # 63 of this thread. Sorry I should have included that.

Ron
 
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icon1.gif


1. Where does the ground go for at line E3 that runs off C3.

E3 and E1 are tide together they are live +

2 " " " " " " " " E5. I'm assuming this is batt neg post.

yes that batt ground


3 " " " " " " " " E7. connect with any other ground

4 " " " " " " " " E8 off of D3.

E8 is the input signal from your hall sensor

5 And finally where does the ground go at E4 off of Q1 where it says "see note 5"

all ground can be attached to the battery but note 5 says to connect both emitter together (the pin with an arrow on your diagram)

hope it help
 
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Thanks Luc, I'm still a little confused though.

On lineE3 there is a component C3 that shows a ground, are you saying it can be tied to the ground at E5?

At line E8 there is a component D3 that has a ground, where does it go?

Also B3 goes to batt., but which ground goes to the engine? and does one get screwed to the distributor?

Thanks for your help on this.

Ron
 
On lineE3 there is a component C3 that shows a ground, are you saying it can be tied to the ground at E5?

Yes the ground of C3 can bi tied to E5

At line E8 there is a component D3 that has a ground, where does it go?

Also B3 goes to batt., but which ground goes to the engine? and does one get screwed to the distributor?

their is only one ground, it's common practice to draw a circuit like this
to only show wires that are important

all ground MUST be tied together on the engine, battery and distributor
 
it should look like this when finish
curious what are you planning to use this on

electronic diagram.jpg
 
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Thanks Luc. Now that makes it much more understandable for me.

Thanks for being so patient with me and making it clear.

Ron
 

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