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74Sprint

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Well I got bugs, surprise, surprise, not. Did a little testing and found bugs in both programs and now I have to debug. I also have a bunch of other things I have to do this week so progress is going to slow down for a little while.

Cheers
Ray
 
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for what it's worth, there is a schematic and a short article on CD ignitions on my web page - I use one of that design on my 356 (that's a car, not an engine displacement) -I put a lot of miles on the car with that ignition, its very simple and reliable - but it does work with a distributor and breaker points. WB Noble article published in Skinned Knuckles Magazine

the page with that article is here: WB Noble article page

there is no software in this circuit, no integrated circuits, just a surplus transformer, capacitor, some diodes, SCR and a couple of transistors. no circuit board either .... The way technology has changed over the last 45 or so years, no?
 

74Sprint

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for what it's worth, there is a schematic and a short article on CD ignitions on my web page - I use one of that design on my 356 (that's a car, not an engine displacement) -I put a lot of miles on the car with that ignition, its very simple and reliable - but it does work with a distributor and breaker points. WB Noble article published in Skinned Knuckles Magazine

the page with that article is here: WB Noble article page

there is no software in this circuit, no integrated circuits, just a surplus transformer, capacitor, some diodes, SCR and a couple of transistors. no circuit board either .... The way technology has changed over the last 45 or so years, no?
Yup I know what a 356 is. I used to work with a german fellow that had one, we used to call it a 356 spider, not sure if it actually was one. As CDI ignitions there are a ton of different designs out there. Here is something very few people know is that the first example and working one was designed by a Canadian air force pilot back in the early 1950's. The design you show is still similar to the one he came up with. I've tried both the Hartley Oscillator & Colpitts Oscillator designs or variations of them but, I didn't like the consistency of them. My CDI design also uses 1,000 - 1,200 volts primary as compared to the 120 - 600 volt ones.

The main idea of mine here is to replace the mechanical advance as inexpensive as possible and stay within the limits of the mcu. I also want to use this design as a interface for standard ignitions. Another way to look at what I'm doing here is that it is a proof of concept for a coil-near-plug design. My final design of the CNP will also have a vacuum/boost reference and a faster MCU >=100mhz.

Cheers
Ray
 
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Ray - you are trying to do something pretty different - in my case the circuit charges the capaictor to around 250 V, that's the typical primary circuit voltage on a spark coil ignition like the 356 (or my old doge) has - I tried higher voltages, it actually didn't work as well, no doubt due to longer recharge times. My 356 redlines at 4500 RPM, so at two sparks per rev (it's a 4 cycle engine, right, and 4 cylinders), that's 150 sparks per second - an easy rate for a modern all digital solution to meet. if you are running a 100 MHz clock and average 2 instructions per clock, you have over 300,000 instructions you can execute per spark - that should let you right one heck of a pile of sophisticated code.
 

74Sprint

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Well this project here is using a 18 MHz mcu and it can fire an LS1/2 (Inductive) coil up to 12,000 cam rpm so that would be 24,000 crank rpm. I know of racers that are using this as a single coil to 7,500 V8 rpm. The spark is actually quite descent up to 12,000 sparks per minute level but starts to die out after 12,500. My little CDI "Sparky" is a little beast but, took some tuning of components to reach the level it does. It can do 51,000 single sparks per minute. I do have a automotive racing ignition in the works that is actually 8 CDI ignitions in one and draws 54-56 amps and outputs 1,200 volts primary, it is also a coil-near-plug design. On a V8 it is capable of 48,000 crank rpm. I also have an inductive multi-spark ignition that draws 48 amps at max setting also tops out at >1,200 volts primary. But this puppy can only run for 15 minutes at max power setting. I've been waiting for 20 years for more reliable electronic components that are just now on the market that can handle the voltage and power. Thanks to electric vehicles. When this ignition is running at 75% power the fuel mileage on my 1976 Ford 302 truck increased by 30% and emissions decreased by @ 60%. I made these measurements using a 1 gallon (imp) jug (28 mpg) and my old tailpipe gas analyser which is now retired. It is a regenerative ignition so any left over energy is applied to the next spark and there is 3-6 sparks per firing not just a couple depending on rpm. We have had the spark top out at 120,000 volts (good for lighting cigarettes) measured with a high voltage probe I borrowed. I've had electrical and electronic engineers say there is no way it will work but, I have witnesses to the contrary. Yah I've been around for awhile and now that I'm retired I'm trying to commercialize some of my work and give a run at MSD. Ah I'll see how it goes.

Cheers
Ray
 

GreenTwin

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I've had electrical and electronic engineers say there is no way it will work
I have had so many people tell me that over the years.
Sometimes they are correct, but very often they were wrong.

The proof is in the pudding.
If you can make it work, then the EE's will do backflips trying to reverse engineer it into equations that explain it all.

Good luck.
.
 

stevehuckss396

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I had gm engineers tell me that an engine with a 5/8 bore and stroke won't run on gasoline. Said I would need nitro. Guess what! My pal still has one of my #8 sparkplugs on his workbench with a .012 inch gap. Again they thought that wouldn't work. Guess what!
 

CFLBob

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The previous experiences from @GreenTwin and @stevehuckss396 reminded me of this great quote from Arthur C. Clarke. Substitute "engineer" where it says scientist and then it goes along with what you guys say.

“When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.”
― Arthur C. Clarke

Ray - my last job before retiring at the end of '15 was designing the RF section of 10 GHz weather radars for commercial aviation, from small jets to Boeing/Airbus air transport planes. What sort of radars were you doing?
 

GreenTwin

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I often hear things like:

1. You can't do that.
2. You shouldn't do that.
3. That won't work.
4. If it did work, you should not do it.
5. How do we change our system so we can do that too?

I also hear:

1. We have never done it that way before.
2. Nobody does it that way.
3. Why would you change something from the way it is always been done?

etc., etc., etc.

When I hear "that is not the way we have always done it", I immediately think "no doubt there is a much better way of doing this", and very often I prove that.

There are many aspects of design.
Some of it has to do with UL listings, and how things are tested, and what may happen if you modify a device to operate outside of its design range.
It is never about breaking the laws of physics, but rather about finding unique arrangements for components and systems.

One story was in Scientific American I think, about an amplifier.
They build two components of an amplifier, and mounted them back-to-back.
There was an unplanned and unintentional induced feedback from one component to another, which produced a highly desirable effect in the amp.
Others tried to copy the design, and were baffled when their designs did not work the same, because the components were not mounted back-to-back.

Edit:

Another example is the story about the famous Russian rocket engine that outperformed any other rocket engine in the world.
The method that the Russians used for this engine was dismissed by NASA, and when NASA finally got ahold of one of these engines after the Soviet Union broke up, they discovered that they were 20 years behind the Russians in rocket engine technology.
.
 
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there is a very gratifying event, if you are able to produce it, and that is when you are a young hotshot, and a room full of self-important senior engineers is working a problem, and you offer a soluton and their leader says "that is impossible" - I still relish the feel of the room, one hour later when I walked back in with a 6 inch thick printout and dropped in in the middle of the table and said "which part of this was it that is impossible?". The "leader" was a leader no more after that.
 

74Sprint

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The previous experiences from @GreenTwin and @stevehuckss396 reminded me of this great quote from Arthur C. Clarke. Substitute "engineer" where it says scientist and then it goes along with what you guys say.

“When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.”
― Arthur C. Clarke

Ray - my last job before retiring at the end of '15 was designing the RF section of 10 GHz weather radars for commercial aviation, from small jets to Boeing/Airbus air transport planes. What sort of radars were you doing?
The RADARs I worked on were all ground based, ASR, IFF/SSR, PAR, Airport Ground/ASR, ILS, TACAN, and man portable. All of it was military except the ILS which was a Philips system. The TACAN is the military version of what the civilians call VDF or direction finder. Obviously I can't get into the details of the stuff but it was cool to be working on stuff that was 15 years ahead of the civilian stuff. The military paid a premium to have the 15 year head start, LOL the $5,000 shovel thingy. I guess you know about high power resonant frequency bursts then? Which inspired my 1 ignition. ASR had Pulsed, CW, and Doppler which was cool. I can honestly say 'stealth my a_s it is', LOL I can see you. I also worked on some phased array stuff and I'll leave it at that. I have seen and worked on some amazing stuff over the years that left a lot of people scratching their heads. After the military I went to work for the railroad and got my AAR electricians ticket and now I'm retired.

We can only create what we can imagine.

Cheers
Ray
 

74Sprint

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I often hear things like:

1. You can't do that.
2. You shouldn't do that.
3. That won't work.
4. If it did work, you should not do it.
5. How do we change our system so we can do that too?

I also hear:

1. We have never done it that way before.
2. Nobody does it that way.
3. Why would you change something from the way it is always been done?

etc., etc., etc.

When I hear "that is not the way we have always done it", I immediately think "no doubt there is a much better way of doing this", and very often I prove that.

There are many aspects of design.
Some of it has to do with UL listings, and how things are tested, and what may happen if you modify a device to operate outside of its design range.
It is never about breaking the laws of physics, but rather about finding unique arrangements for components and systems.

One story was in Scientific American I think, about an amplifier.
They build two components of an amplifier, and mounted them back-to-back.
There was an unplanned and unintentional induced feedback from one component to another, which produced a highly desirable effect in the amp.
Others tried to copy the design, and were baffled when their designs did not work the same, because the components were not mounted back-to-back.

Edit:

Another example is the story about the famous Russian rocket engine that outperformed any other rocket engine in the world.
The method that the Russians used for this engine was dismissed by NASA, and when NASA finally got ahold of one of these engines after the Soviet Union broke up, they discovered that they were 20 years behind the Russians in rocket engine technology.
.
I use to work with a fellow named Joe Mazelli, bless his soul (RIP), said to me once "that's the way we have been doing it for 20 years". I said to Joe "did you ever think you were doing it wrong for 20 years?", he went silent.

Necessity or money is the mother of invention. We either figure it out, stumble upon it, or just look at it in a different way. I have been in meetings where someone suggests something, they get laughed at, at first but, then wouldn't you know it, they ended up being right. So I always try to keep an open mind.
Old age has given me knowledge and I hope wisdom.

Cheers
Ray
 

74Sprint

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there is a very gratifying event, if you are able to produce it, and that is when you are a young hotshot, and a room full of self-important senior engineers is working a problem, and you offer a soluton and their leader says "that is impossible" - I still relish the feel of the room, one hour later when I walked back in with a 6 inch thick printout and dropped in in the middle of the table and said "which part of this was it that is impossible?". The "leader" was a leader no more after that.
LOL, been there done that, unfortunately too many times. My most gratifying time was when I was still a private and found the problem with the rotary joint on the ASR RADAR, a $100,000 part (back in 1983) was changed out and modified on my suggestion. The lubrication ( organic grease) was interacting with the microwaves getting turned into carbon and the hard chrome finish on the roller bearings was getting blown right off like when you put aluminum foil in a microwave oven. They switched to my recommended lubrication and saved the government a $1,00,000 dollars that year alone. I got promoted to corporal, yippie The big engineers couldn't figure it out. Like really guys, do you really think that a rubber seal is going to stop all that energy.:)

Cheers
Ray
 
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The RADARs I worked on were all ground based, ASR, IFF/SSR, PAR, Airport Ground/ASR, ILS, TACAN, and man portable. All of it was military except the ILS which was a Philips system. The TACAN is the military version of what the civilians call VDF or direction finder. Obviously I can't get into the details of the stuff but it was cool to be working on stuff that was 15 years ahead of the civilian stuff. The military paid a premium to have the 15 year head start, LOL the $5,000 shovel thingy. I guess you know about high power resonant frequency bursts then? Which inspired my 1 ignition. ASR had Pulsed, CW, and Doppler which was cool. I can honestly say 'stealth my a_s it is', LOL I can see you. I also worked on some phased array stuff and I'll leave it at that. I have seen and worked on some amazing stuff over the years that left a lot of people scratching their heads. After the military I went to work for the railroad and got my AAR electricians ticket and now I'm retired.

We can only create what we can imagine.

Cheers
Ray
TACAN = Tactical Air Navigation (Wikipedia, on Tacan) is really the Mil version of VOR (Very High Frequency Omnidirectional Range) which basically gave you the bearing from where you are to the station, often combined with DME (Distance Measuring Equipment) that would give you the range to the station. VOR based navigation is mostly obsolete now that everyone has GPS, but it was common in and equipment to navigate using VOR (called RNAV or Radio Navigation) was a predecessor to INS based navigation. I say this to try to correct VDF as an acronym and in some slight way differentiate TACAN, VOR, and DME.
 

74Sprint

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TACAN = Tactical Air Navigation (Wikipedia, on Tacan) is really the Mil version of VOR (Very High Frequency Omnidirectional Range) which basically gave you the bearing from where you are to the station, often combined with DME (Distance Measuring Equipment) that would give you the range to the station. VOR based navigation is mostly obsolete now that everyone has GPS, but it was common in and equipment to navigate using VOR (called RNAV or Radio Navigation) was a predecessor to INS based navigation. I say this to try to correct VDF as an acronym and in some slight way differentiate TACAN, VOR, and DME.
Yah there are different names for it. But they all basically did the same thing which was to tell pilots the direction to the airport and most did the range and station ID. Don't forget there is also the marine version also. Here is a quark for TACAN; they are vacuum tube based for the reason that an EMP will only knock them out temporarily and they will recover, unlike IC based equipment. Even if the IC equipment is radiation harden. There is a aero supply company "Aircraft Spruce" that I get some metal and stuff from and they pretty much only supply GPS navigation stuff now.
I'm sorry, I have a somewhat dry sense of humor, I read:


and I would add "of course not, to do that you need a rubber chicken".
LOL so true.

Ray
 
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geez, the rubber chicken comment makes no sense with the blank quote box - score one for the computer - in the blank quote box for what I read, it would have a quote from upthread about a rubber seal
Tossing a rubber chicken into the mix ALWAYS makes sense, even with no context :)

I guess you could make one with silver fiber fill and use it for an RF gasket of sorts for those who do need context...

Cheers,
Stan
 
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