Why is it that everytime someone comes up with a workable CDI ignition they have to go nuts and start seeing dollar signs? Then go into endless development- paring down the design til' it hardly works and finally declare they are "in business" and then get a flood of orders that they cant keep up with- then 2 months later give up and quit selling altogether?
Someone needs to give up a solid design- PRINT IT RIGHT HERE ON THE BOARD- with easily sourced parts- for the good of the community. It's not like everyone on here has the capability or desire to assemble one anyway- it is not gonna "kill" the well established ignition makers.
But alot of us do want to make our own. And would if a proven design were available- and I ain't talking about those same old sketchy designs people get pointed at when they ask this question- if that crap worked- we would all be flying it-

A simple CDI with good, efficient characteristics- and maybe upgradable to add an advance feature for the more accomplished builder.

There is no reason why one should cost more than 25-40 bucks total if you sourced the parts and built it yourself. Most of us have half the parts already lying around.

The day is getting near, when some small engine will have compact CDI on it already. Then all you will have to do is transplant it to your favorite engine. Capt,n

C&H and RC ignition have been in business for around 20 years..We tried "Blue Light specials" a while back...Less than 10 were sold at about $35......My toroid coil alone costs $16.00.....If you can find a cheaper alternative, have at it, I will sell no more "Blue light specials" and am now concentrating on Zenoah conversions....
Endless development ? EXACT same circuit for the last 18 YEARS..
I will go out of business the day I die, I'm 70 years old today....

Lessee...Cut and machine the mount, hub, and carb mount...Assemble the CD ignition circuit, put everything together, and test run the engine..Charge a fair price for labor..
I started out 18 years ago charging $150 for a G62 conversion...The price today is STILL $150...I sure am getting rich doing this.....
You cheapskate compainers are welcome to put it where the sun don't shine

hippy pappy bthudmth, Ralph.
have a day off

Happy 70th Birthday Ralph! [sm=thumbup.gif] Many more.

Bruce

this thread really cracked me up especially when i saw the phrase you have under your name. for one thing to the originial post i being one to has soldier many a cable or chip board together in hopes of saving money well i say dont do it! i have probably spent more many than i can count on trying to save money on something. the originial poster might as well try soldiering his own radio gear together. and maybe one day someone can bring the price down further but until then sometimes there is being too cheap. and i should know i am too cheap i can spot our own.

Ok- #1- I'm not talking about assembled products or even kits- I'm talking about circuit diagrams. The need for there to be access to one that actually will perform as intended if built correctly.

This post was not in any way aimed at C&H or RC ignition- I am fully aware of the history, good value, and reliability- I have never heard anyone say a bad thing about them so certain individuals please don't take offense.

I am talking about random individuals who come up with designs that are cheap and they say works- and everyone on the board is like " I want one!!" "me too!!!, me three" That kind of thing- I have seen it quite a few times.


Cheapskate complainer? Why? cause I want a circuit diagram that works to assemble an ignition from? - this isn't the first time a lecture has come down pretty hard when someone posted about searching for a schematic.

why didnt you say you just want open source?

for those of you who dont know what i am talking about www.opensource.org

The advice I'm getting seems to be "you'll be wasting time and money to try anything other than just going ahead and bending over and paying the money for it". Well, fine, maybe it is more difficult than I am thinking it is. But- I will have to be convinced of it myself.
Build radio gear? No way- an ignition? Sure. Thanks for the vote of confidence- learn how to write.

i am a programmer and most of my writing consists of if blank = notblank then //do something end if so you can see writing is not my strong suit. i am not trying to discourage you but it seemed by your tone that all of the people making CDI ignitions were retards and you could do it better yourself. also people have posted links to schematics so if you look in some of the posts you might find what i am talking about. i just was pointing out that if you think you can do better than C&H who have experience with these ignitions you are going to be just one of the other guys on here with dreams of building a better ignition. but i did see by your later post that you were asking for a diagram of a working CDI to build yourself so you didnt have to buy one from someone who really doesnt know what they are talking about. i would tell you the same learn to write. your tone was that like i said early in this post. the links i mentioned earlier are a good start to what you want to do. but if i had a choice between buying a C&H or RCIGN1 original or building i would rather buy it. i would be wasting my time trying to come up with something like they have built. but if you are talking about building as aposed to buying one i built i can see where you are coming from ha ha.

Hollbrow have you read through the scratch built ignition thread, somewhere on there is a link to a cdi circuit that works with components that are easy to find and ferrite core from old computer power supplies, It is certainly not impossible to make your own cdi and it is unlikely to cost more than a prebuilt one. You will probably still need to buy your coil from ch. ch have kits for a building your own ignition if i am not mistaken

Good luck I hope you will share your experiences.

Here it is http://home.online.no/~jon-mj/cdi_ignition.htm

If you insist on doing things the really hard way.
September 1988 RCM has the parts list,schematic, and board layout.
No I can't publish it because it was copyrighted,,, so start digging

sometimes it has nothing to do with price and everything to do with the challenge and just plain love of tinkering. sure i could fork over what CH charges and just be done with it but where's the fun in that? right now i'm having great success with the RCM ignition posted in the DIY thread and more importantly i'm having FUN. time isn't always $$$, that's why it's called a hobby...anybody who tries to build their own ignition with the sole emphasis on saving a buck WILL be very disappointed in the end...


and BTW, i did solder everything in my transmitter and even built the case from aluminium sheet. it blows away any modern radio when it comes to flexibility and programming ease, even does things the futaba 14MZ users can only dream of. cost me less than $100 in parts but also took at least 100 hours of tinkering to get it all together...yet another hobby...



dave

Thanks Rupurt- that is the sort of reference I am looking for- I was just hoping some more people that had tried it would come forth and give experiences. That design is certainly simple enough to
put together in an evening. I may try it. I have studied the RCM design a few years back- I can't remember at the time what kept me from wanting to try it. I'll take another look at it.
Carlosponti- you say you are using a design based on the RCM one? Any thoughts or pointers on it?

More than anything, like Carlosponti said- I like to tinker- and I also get a thrill out of doing it myself. I am just fiddling around with chainsaw and trimmer conversions with very inexpensive
airframes- just looking for a way to keep the cost of an ignition somewhat in line with the rest of my gear. If I can figure out the technology, I can then work on getting some of the cost out of it.
Maybe I can, maybe I can't- but I'll learn something along the way. Thanks for the input guys- anyone else tried any circuits and had good luck with them?

i wanna rant on the 14mz why would any NORMAL person buy one of those. 2500 dollars i believe was the cost.

btw i was pointing out that it would have been more polite to ask for diagrams. you posted a rant about other peoples ignitions. if i was a person like RCIGN1 i would be insulted. i was making light of your originial tone. that and the fact your comment about seeing dollar signs became RCIGN1's little tagline under his name


btw zagnut arent you the guy who posted the senior telemaster? how did all that go? i couldnt find a post by you again.

Yeah- looking back on it- I can understand RCIGN1's point of view- but I wasn't even thinking of them when I made the post. How many times on this board and others has someone said- "new CD ignition almost finished!" Given a bunch of specs, suggested a low price- said they are "refining it" then just kinda faded away? I think there is a thread similar to that on this forum now. That's all I meant to rant about. Seriously- I meant no insult to those who have established bona-fide businesses selling these systems.
I just want a circuit diagram of a system that several people are using that seems to work well.

Zagnut, are you using a hall type pickup with the RCM circuit on the one you said you were having good luck with? Did you have to modify the circuit for it? What coil are you using?
Thanks

i have been curious myself about creating one to try it. i need to get the dust off my soldiering iron i havent burned myself in a while he he.

RCIGN1....HAPPY BIRTDAY ...Hope to be reading your posts for years to come!!! I keep posting here to buy your ignition ....not a better one for the $$$ with the best guarantee. Take Care Capt,n John

yes, i'm using a hall sensor with the RCM ignition, just delete the buffer IC needed for points. basically the same schematic as the one Rupurt linked to above. spark coils are from 3W ignitions or hand wound copies, info is from about post # 300 and on in the "scratchbuilt ignition" thread. this is the CDI published back in 1980 and not the one from '88 that tkg mentioned, would really like to see those schematics though.

don't know exactly which hall sensor i'm using but it's the type that needs two magnets, one to turn it on and one to turn it off. the reason i used this is because it can work at lower voltages than the ones used by CH and RCIGN and allows me to run the ignition from a single lipo cell.

and no, i've never had a telemaster



dave