RE: New CDI - opensource project JMJ and Bigboat
 

You need a unipolair hallsensor.
Bipolair needs a switching magneticfeeld N/S/N/S to switch, unipolair not.
Choose a higer voltage for the hallsensor then your batterie voltage, 4,5 till 6 Volt isn't high enough.

RE: New CDI - opensource project JMJ and Bigboat
 

Hello Rob
I feel more informed in my searching for the hall unipolar type

Also available locally is this

IC, sensor, Hall Effect, unipolar, SS443A
Details from data sheet

Am I close to the correct type

cheers Jeff

RE: New CDI - opensource project JMJ and Bigboat
 

You can use this one without any problem.

RE: New CDI - opensource project JMJ and Bigboat
 

Thankyou Rob

I have spent day going around in circles looking at available online Australian electronic shops

I find to my embarrasment that the final hall was originally listed on the original site:-
http://home.online.no/~jon-mj/cdi_ignition.htm

Now to find most of other components_
have found Bt151 locally

Your circuit lists "Flashlight" is this a led or incandescent?

Any thing special about opto TIL111 "standard led photodiode"?
here i find 4N28/4N25

it appears similar except the pin 2 is anode and pin 3 is cathode
wheras til111 has pin1 anode and pin2 cathode from research?

cheers Jeff

RE: New CDI - opensource project JMJ and Bigboat
 

It's a bright-LED (they call it whitlight-LED)

Any opto is good, I was using TIL111 and 4N25.

Yep.

RE: New CDI - opensource project JMJ and Bigboat
 

Thanks again Rob
Im getting closer:D

Capacitor for storage C6 is what we call
Greencap, Polyester or"Mylar"
I have found 630v dc 470nf 26mm lead spacing ?


L4 1uH is this a RF Choke type?

IC3 LP2950CZ from specs is 100maH +5v
I have found similar 78L05 100maH low power

This leaves just the capacitors and resistors
plus programminf pic (next week!)
and pc Board

cheers Jeff

RE: New CDI - opensource project JMJ and Bigboat
 

Any type is good if the voltrage is high enough > 400Volt

Yep and it lookslike a 1/2 Watt resistor.

A 7805 doesn't work becourse the voltagedrop is to high (3 Volt)
If the voltage from yor batterie is 6 Volt, after the regulator it's only 3 Volt.
You realy need a type with a voltagedrop >/= then 1 Volt.

BTW, why don't you sleep......it's now 17 h in the Netherlands, I acpect it about 5 o'clock in Australia (?)

RE: New CDI - opensource project JMJ and Bigboat
 

Thanks Rob
Sleep soon- now 1.30am - home with a brocken arm plenty of time off[:o]
(fell of my nice BMW bike)

Last for today
I find cheap JDM programmers on Ebay - will research later.

I can see 16F628A pic not 16f628 - will reseach to see if compatible with your hex?

cheers jeff

RE: New CDI - opensource project JMJ and Bigboat
 

Build your own programmer, it's not diffecult.....only a few componets.

The A-type is OK, I forgot to write the A into the schematic.

RE: New CDI - opensource project JMJ and Bigboat
 

Hello Rob
On the schematic the capacitors c3,c7 are listed as 0.1u (100n) + (electro type?)

These have been difficult to find - must be looking for the incorrect thing?

Could these be replaced with greencap "mylar" type similar to the c8,c4,c5 100n

cheers Jeff
ps found the low drop out 5v regulator:)

RE: New CDI - opensource project JMJ and Bigboat
 

Guys.....there is a lot of talk about electroniccs here. What some us wants to know does this system work good for airplanes? Also what is the cost of the ignition system ready to go? Thanks Capt,n;)

RE: New CDI - opensource project JMJ and Bigboat
 

Yes a lot of talk about electronics.
It is an open source project where this talk helps develop the goal to a DIY CDI for engines.

I take it on faith that it works.

The original thread (see page1) shows video of strong spark and success with the project
Rod has his mounted on a gas engine - see page1 of this thread.

Cost? This is DIY so far around $30AUS plus 3 days of research (priceless!)

it is cheaper to buy completed project ie Desert Aircraft, CH, so on at $200 or more if you want it now.

cheers Jeff

RE: New CDI - opensource project JMJ and Bigboat
 

What's the feasability of using an optical sensor in place of the hall effect sensor? similar to what they do to sense engine RPM with some tachs? it would just require painting the flywheel white and black, and possibly a small LED for a light source. I want to build a CDI for a small engine, but without removing my magneto (it supplies accessory power as well) and the stock flywheel (with two magnets).

RE: New CDI - opensource project JMJ and Bigboat
 

Replying to myself - did a little research tonight, and it seems the recommended hall sensor outputs a mere .4v - would it be possible to use this optical sensor ( http://www.taosinc.com/images/produc...rs17xx-e14.pdf ) with it's output of ~2v nominal? I know it's not a focused type sensor, but it should work fine if placed within 1-2mm of the flywheel. There's another sensor that could be used - but instead of a straightforward output voltage, it has a phototransistor and while I can troubleshoot a dead circuit, I have no idea how to wire this in to work as a switch - ( http://www.optekinc.com/pdf/OPB740.pdf )

Any help would be great, otherwise I'm willing to just try it on.

RE: New CDI - opensource project JMJ and Bigboat
 

@tomservo,

Why will you risk false light to stop your engine with a opto ?

RE: New CDI - opensource project JMJ and Bigboat
 

I have spark- ouch!

All very messy at the moment:eek:

Operating at this stage without scr by earthing the capacitor C6 to earth to generate spark.

Using 4 cell nicad (5.2v) - I can get a solid spark every 1 sec?
Faster tapping to earth doesn't generate more sparks.

At this stage many unknowns -

4 cell nicad sufficient?
100n = 0.1u c7 greencap/mylar sufficient - OK?
0.15mm to wind 400 turns L1 and 8 turn L2(my mistake should have used 0.2 on circuit)
scr BT151 will be inserted when I can work out triggering before pic arrives and is programed
Is 5v sufficient to trigger scr?
Use of cheap ignition coil from pocket bike? - Need to order CH coil!

Before I was convinced I had a working circuit - a strong shock woke my brocken arm up[X(]

Poor quality photos from web cam showing circuit and coil.

Cheers Jeff

RE: New CDI - opensource project JMJ and Bigboat
 

I use 5 cells, but 4 cells are enough to test.

Thats not the problem of your powersource, but your fastness :)

0.1 uF is a littlebit low, use 470nF/400VAC / 600VDC atleast

No problem, have to work.

5 Volt is (to) high for a BT151, he will ignite on 0.8 Volt allready (don't forget a resistor into the gate!)

Why to order a new coil, I use also a cheap pocketbikecoil.....BUT, don't forget to ground the metal of your coil to the sparkplug and powerboard, otherwise it isn't work !!

OEPS.......[&o]

RE: New CDI - opensource project JMJ and Bigboat
 

Thankyou Rob

>0.1 uF is a littlebit low, use 470nF/400VAC / 600VDC atleast
0.1 shown on circuit diagram will try larger value- off to the shops in the morning!


>5 Volt is (to) high for a BT151, he will ignite on 0.8 Volt allready (don't forget a resistor into the gate!)
I will include r3, c3 and r4 onto test board and use this to trigger.

> don't forget to ground the metal of your coil to the sparkplug and powerboard, otherwise it isn't work !!

Thankyou- I was carefull to do this - I get a solid spark but tapping faster than 1hz shows no spark.

cheers Jeff

RE: New CDI - opensource project JMJ and Bigboat
 

Rob: On the engine I want to put this one on, the area around the flywheel is enclosed and no light will enter. So for this case, it could be a perfect solution... Since I have to keep the magnets on the flywheel. I can just paint the flywheel black and use a white line to trigger. (or vice versa, as the case may be) Now, on my G23 in my boat, I will use a hall sensor :) Any idea if one of those sensors I linked to will work? I can't even put the hall sensor on the other end of the crankshaft, as there is a gearbox there..

RE: New CDI - opensource project JMJ and Bigboat
 

Don't forget, you have to adjust (~40 degrees BTDC) the (any) sensor befor you can use the cdi.
Any sensor will do the job, also optosensors, but choose a IR-sensor not a normal LED-opto.
The switch between high low is the point to go into the advangetable of the cdi.
If the window of the sensor is 5mm befor swithing, you have to notice you have to calculate this distance (=time) within you timing.

RE: New CDI - opensource project JMJ and Bigboat
 

Good to hear! Thanks, Rob! For future searching, is any particular voltage level necessary to trigger the advance?

RE: New CDI - opensource project JMJ and Bigboat
 

You have to notice, a trigger is a digitalsignal (0 > 5 > 0 Volt) and not a analogsignal.
If the signal is analog, _somewhere_ in this analogsignal you reach the triggerpoint, but when do you reach this point.
There are optocouplers with a trigger output, I don't know witch one.
Normaly the half of the source voltage is the trigger voltage.

RE: New CDI - opensource project JMJ and Bigboat
 

Thanks again, Rob - I found an application diagram showing the optosensor being used in a logic level circuit exactly as we are using the Hall sensors - but with a 15k resistor to ground instead. So I'll order a 10k and a 15k resistor and see what works better...

I should be able to trigger by painting the flywheel black except for a small (trigger) section which i can paint white or polish. The resolution of the sensor is ~1mm so I shouldn't run into problems with timing it. I'll let everyone know how it goes once I've gotten it all sorted out.

RE: New CDI - opensource project JMJ and Bigboat
 

Hi Rob
I wonder is this C7 you are suggesting to be "470nF/400VAC / 600VDC" it looks more like C1?

I have used greecap/mylar type for C7 0.1u as per circuit diagram - is it correct to change this to 470nf (0.47u)?

cheers Jeff

RE: New CDI - opensource project JMJ and Bigboat
 

You're right, it have to be 0,1 uF/16Volt type.
I got a old schematic, not the new one I put on my site, sorry.