Maku

Hi hogboy,
I am also new to this forum and trying to build the CDI too. The excel sheet has an error on the command DEC to HEX. The solution from lumpylumpy is given below.
Could you give some more information on your Transformer, and some specs on the core (core size, type, producer etc)??

Maku.

Hi,i had problems with the exel sheets too,have instaled office severel times,instaled all addins and still not worked! then i did a little research and found out that there is a little error in the formulas calculating the lines for the asm. ; this is how it should loke like =IF(B16<$D$8,CONCATENATE(" ",$E$14,DEC2HEX(D16),$E$15,$A$142,ROUND(D16/10,1),$A$149,INT(B16),$B$14))
and this is how it loked originaly =IF(B40<$D$8,IF(D40>10,CONCATENATE(" ",$E$14,DECHEX(D40,2),$E$15,$A$142,TRUNC(D40/10,1),$A$149,INT(B40),$B$14),CONCATENATE(" ",$E$14,DECHEX(D40),$E$15,$A$142,ROUND(D40/10,1),$A$149,INT(B40),$B$14)),$E$16)
i have deleted a portion of the formula,and where it writes dechex i have replaced it with de2hex,as you could notice in the formula! you have to have the next addins instelled:anallysis toll pack and solver add-in!!!!!!!
you copy the formula in to the first line off the exel (cell e16) and press enter;after that copy/paste on each line until finsh(do not paste severel lines at once, one line at a time so you dont have to modify the formula!!!!)
this is made for the exel map 42 ;you can do the same with the other exel maps,but the formulas not the same! so be careful what you delete from the formula!!!
I hope it helps you,and i did not write it two complicated!I am not so good at english.

rpm adv. nr loops lines to insert into asm.
1,010 6.0 50 retlw 31h ;5ms 1010rpm 1,010 6.0
1,017 6.3 49 retlw 30h ;4.9ms 1016rpm 1,017 6.3
1,024 6.5 48 retlw 2Fh ;4.8ms 1023rpm 1,024 6.5
1,031 6.8 47 retlw 2Fh ;4.7ms 1030rpm 1,031 6.8
1,038 7.0 46 retlw 2Eh ;4.6ms 1038rpm 1,038 7.0
1,045 7.3 46 retlw 2Dh ;4.6ms 1045rpm 1,045 7.3
1,053 7.6 45 retlw 2Dh ;4.5ms 1052rpm 1,053 7.6

this is how it should look like.
Regard ,Zoli.

KI8FR

It is a good thing some one know how to read that. lol....
I was thinking of trying to make me one but as I read on I does not look to be a ez thing to do..
I will have to do some more reading.
Paul

acgeorge

My Feedback: (3)

Looks like the CDI's are finally becoming available. BCMA has them for $85 w/auto advance.

[link=http://www.bcmaengines.com/BCMAProducts.htm]BCMA[/link]

jpanhalt

Can any of the commercial units be user programmed? Thanks. John

RysiuM

My Feedback: (1)

Reading instruction I found funny thing (maybe it is not quite funny, but plain wrong).

The last "extreme" is a real hardcore. The most stupid thing would be masking interference by using PCM. [:'(]

captinjohn

Forget the...PCM...Get a Spectrum spread 7 channel Radio and give that a try! Capt,n[:-]

PilotTiger

My Feedback: (3)

BigBoat, is it possible that you have an error on your web page and that when one clicks on the incircuitprogramming the small pcb layout comes up?

Yoram

Bigboat

I don't know, wat pic do you mean ?

This one is the incircuitprogramming



And this one not

PilotTiger

My Feedback: (3)

BigBoat, if you go to your page http://www.modelbouw.gompy.net/cdi/cdi.htm the "Layout small PCB" and the "Layout small PCB for incircuitprogramming" comes up the same. Didn't you had a layout for a programmer or was it only a figment of my imagination? I don't mean the link to a programmer that you have on the new cdi page.

Yoram

PilotTiger

My Feedback: (3)

Also, in the new cdi, if I don't want the flash, I can take out the transistor too, right?

Bigboat

Both pcb's looks the same, but the pins are differend to the 16f84.

Bigboat

You can take out the transistor, but it's very handy to use for timing the engine.

KI8FR

I was not able to find any thing in this form on the fly weel.. what do I have to do about a fly weel.

Bigboat

Nothing.....you don't need it anymore if you gone use a prop.
You have to put somewhere a small magnet, but not into the flywheel becourse he is magnetic too.
The hallsensor must be placed about 40 degrease BTDC.

KI8FR

one of the things Im trying to do is take off the big fly wheel.. It will not fit under the cowl I was thinking of training the fly wheel down and put the magnet in it. I just do not know if I will have probs with it if I do that..

Bigboat

The flywheel is not only for the ignition, but it helps also the engine a littlebit with the rotation.
The crank only itn't enough to let spin the engine, he needs also the (rotation) weight of the flywheel.
The prop is taken over the (rotation) function of the flywheel.

KI8FR

Ok so your saying that I do not need the fly wheel cuz the prop will do the work?

captinjohn

What I do is use a hole cutter in a drill press and cut out the center of the flywheel. Takes only about 3 min. Then I take and place the center of the flywheel and place it on a mandrel in metal lathe and cut to shape. You can add your magnet for the pick-up in a small hole drilled in hub. Good Luck......Capt,n

KI8FR

Now that is the info I was looking for... I have not make a cdi yet Im still in the studding part of it.. It does not look that hard to do but well you know how it is lol
Paul

epilot

I have all the components, now I just need to etch the PCB and wind the coils. I agree that winding a toroid is a royal pain in the behind. Does anyone have a source for E cores and coil formers? I have a CNC coil winder so as long as I can get a hold of the formers, winding is a breeze. Maplins in the UK sell Velleman kits but NOT the FLPS

Michael

panyasx

derek4210

All you that are building the CDI please post on how well your engine runs. Also anybody who is interested, I slightly redesigned the above CDI project. I am using the TI MSP-430 micro-controller IC. This is so much easier to control your auto advance. Just a P.C /laptop w/USB port running hyperterminal allows you to change your auto advance timing settings in Flash Memory. Also there are no limits on what else you can dream up.

Derek.

jpanhalt

Derek4210,

Can you post the code for that microcontroller? I am a relative newbie with PIC and have no experience with the TI product. I also live pretty close to you. PM, if you want to discuss.

John

dinoslmn

My Feedback: (1)

Try following link. I received 3 pcs two weeks ago. $5.99 / each
http://www.hobbyengineering.com/H1958.html

Bigboat

Beware........not all coils can handle the high rpm......you need >15.000 rpm for a stock Zenoah.
Only weedeathers running slowly until 10.000 rpm.