Have fun.

The CNY17Fcomes in 4 versions, CNY17F-1, CNY17F-2, CNY17F-3, and CNY17F-4. The CNY17F-1 has the same specs as the 4N25, you could also use the -2 but, the -3 and -4 have a transfer ratio of over 100% and can be over sensitive. Also, almost all manufacturers recommend that the RL, R11 in Gompy's schematic be between 75 and 100 ohms. The higher the resistance the slower the transistor in the opto switches. Also Vishay shows using a 50 ohm LED resistor with a 5v supply, I believe these values will solve the switching problems.

Ray

These are the optoisolators with out a base terminal/pin that Digi-Key has that should be compatible with the 4N25.

Digi-Key Part Number - Manufacturer Part Number - Manufacturer
751-1338-5-ND ______MOC8102 _______________Vishay Semiconductor Opto Division
751-1337-5-ND ______MOC8101 _______________Vishay Semiconductor Opto Division
751-1269-5-ND ______CNY17F-1 _______________Vishay Semiconductor Opto Division
751-1270-5-ND ______CNY17F-2 _______________Vishay Semiconductor Opto Division
160-1318-5-ND ______CNY17F-2 _______________Lite-On Inc
160-1316-5-ND ______CNY17F-1 _______________Lite-On Inc
CNY17F2MFS-ND ______CNY17F2M _______________Fairchild Optoelectronics Group
CNY17F3MFS-ND ______CNY17F3M _______________Fairchild Optoelectronics Group
CNY17F2TVM-ND ______CNY17F2TVM _______________Fairchild Optoelectronics Group
CNY17F3TVM-ND ______CNY17F3TVM _______________Fairchild Optoelectronics Group
CNY17F1MFS-ND ______CNY17F1M _______________Fairchild Optoelectronics Group
751-1339-5-ND ______MOC8103 Vishay _______________Semiconductor Opto Division
425-2155-5-ND ______PC714V0NSZXF _______________Sharp Microelectronics
TLP632GBF-ND ______TLP632(GB,F) _______________Toshiba

Ray

Have fun.

Originally Posted by Gompy

Try again, but I'm only the guy who designe the boards.

The PDF that this link http://www.farnell.com/datasheets/90931.pdf opens is the only one I have seen that shows the resistance, even though it is or was a Vishay data-sheet. To bad I didn't read that one, I read the Vishay produced one. Good catch Gompy.

Ray

Even using their specified resistances the opto is sporadic in operation with the board. I will go back to the 4N35 I was using, the board functions fine with only the one glitch.
I'm not building any more ignition board circuits. Tired of all the wasted parts and time involved. If someone comes up with a better board that is both more efficient and more powerful, so be it. Use that board. I am not in this to be a competitor, just offered what I make. I have hundreds out there that are working fine with little or no RFI problems. The stronger the spark a board produces, the more chance for RFI. There is a cut off point for performance versus RFI problems. I don't care to argue this point anymore. If what you build is working, then use it.
I'm not trying to reinvent the wheel. My time is better spent making proven circuits that are trouble free.
We have a timer board and various HV board designs to choose from as evident by the posted schematics. I would rather see new ideas with off the shelf parts available than have someone condemn the work Rob and I have done in getting this ignition thread started. There are those who seem to forget, this information was all given for free to share a good thing with fellow modelers.

Just my 2 1/2 cents worth

John

Originally Posted by gr8flyer55

Even using their specified resistances the opto is sporadic in operation with the board. I will go back to the 4N35 I was using, the board functions fine with only the one glitch.

It seems the board works fine so long as you don't hold on to it. Which will never happen in a real life situation.

I'm not building any more ignition board circuits. Tired of all the wasted parts and time involved. If someone comes up with a better board that is both more efficient and more powerful, so be it. Use that board. I am not in this to be a competitor, just offered what I make. I have hundreds out there that are working fine with little or no RFI problems. The stronger the spark a board produces, the more chance for RFI. There is a cut off point for performance versus RFI problems. I don't care to argue this point anymore. If what you build is working, then use it.

I agree John with the RFI, been there done that. Beside I thought your ignition was originally designed for doing conversions on wacker type motors, which very rarely go over 10k rpm. So don't fix what ain't broke.

We have a timer board and various HV board designs to choose from as evident by the posted schematics. I would rather see new ideas with off the shelf parts available than have someone condemn the work Rob and I have done in getting this ignition thread started. There are those who seem to forget, this information was all given for free to share a good thing with fellow modelers.

Just my 2 1/2 cents worth

John

Yup, it's open source, take what is given and make it your own. I believe IHMO that because it is open source everone should have a different setup, that is how we learn.

Ray

P.S. I'm still going to use the 2 you sent me, whenever customs is finished with them.

Ray, I can't believe they are still holding them in customs. Maybe they are trying to copy my circuits? LOL

John

The stumbling block for almost all DIY HV designs is definitely the transformer. If someone has the time to do a bit of research, we need an easily obtainable transformer that needs little or no rework of the initial primary windings. On my design, the windings are 400 secondary, #36 awg, 16 primary, #26awg, and 8 feedback, #32 awg. A transformer with these figures is very difficult to find. That was why I used a toroid which was hand wound. It is time consuming, very tedious work, but if wound correctly, with near perfect spacing, it is a very efficient design transformer and the cores are cheap. I can buy a pack of 10 cores at Radio Shack stores for a few bucks. There are 2 different sizes in that assortment. I have tried both and had successfully wound both sizes. I would prefer to just order an ecore based unit but finding the right one is very confusing. The ecore size you would need should be in the E-14 to E-16 size. Anyone have either a part number or a place to get them?

John

Originally Posted by gr8flyer55

The ecore size you would need should be in the E-14 to E-16 size. Anyone have either a part number or a place to get them?

Hello to everyone.

Hi John

I EPCOS (TDK) offering.
The N27 and N87 ferrite cores recommend it.
The N27 is cheaper.
Link:Ferrites/Materials
Link:EELPCores


Regards nyemi

Originally Posted by gr8flyer55

The stumbling block for almost all DIY HV designs is definitely the transformer.

I think your design works just perfectly for me. If we can just standardize on an E-core I think we can convert the turns to wire lengths. Then if we (by we I mean you) write up a good set of instructions, it will be fairly easy for a new user to do the winding.

Then one of us can buy some big spools of the wire, cut off the right lengths, and put them together with a core to make a complete DIY transformer winding kit.

Once that's done I think we can put together kits very easily. All the winding work will be farmed out to the end user, and they get the fun of learning to wind a transformer!

The transformer winding part put me off at the beginning, because I've never done it before. But if everything it worked out to a T, I think it would be fun and easy. Most of the pre-fab transformers I see are way to expensive compared to the actual cost of the core and wire, and I wouldn't know how to pick the right one anyways.


-Jake

Rob/Nyemi
Could you look at these and see if they will do.
http://australia.rs-online.com/web/p...cores/6479575/

Have fun.

That is a 20mm core. While it would work fine, still a bit large. The one I use now is only 14mm and gives just enough space around it for inter wiring and other components. Maybe I'll have to try the 20mm size and enlarge the board 5mm to make it fit. On that site, I found a B65808E150BT1 8 pin, round core, halves held together with a 3mm screw. That looks promising too since you can run the bolt thru the board to mount it. I don't know which would be better. I tried a 20mm on my boards and it looks like an elephant on a tricycle. I'd have to post a picture to show what I mean. The toroid I also use is only 1/2" in diameter and after winding it with all the wires is still only .625" diameter and 1/4" high laying flat to the board.

John

Originally Posted by Gompy

Order transformers from John or Adrian.

That would be fine by me but John was saying he did not have a ferrtie E core standard to use, that is why I looked and suggested what I did.