your own ignition

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Re: your own ignition

Post by minetymenace »

Yes your resistor values look right. The point I was making was that your low voltage and high voltage are not isolated....maybe this isn't important yet. As the secondary is only a reflection of what is on the primary, you could take your feedback off the primary (low voltage cap, and regulate to 12v) and rely on the turns ration to give you your isolated 400v on the secondary.

The dots, maybe this will explain:
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Re: your own ignition

Post by stew79 »

beat , this new thing you are sorting out is to clever for me. i dont no how your transformer is wound or connected. i hope it will be worth the effort. my experiment to convert a low voltage oscillator from a tessla project, to run a cdi has had some knock backs. it dosent like having 12 volts through it, even with the extra turns on the primary and a range of different resistors for the feed back. i wound up another smaller coil to try but this has the same problems, the ac tvs,s turned up today so i can select what voltage i think i need and both coils have been on the test rig , not good enough (happy on 3 volts but cant run over 4000 rpm) the feed back coils will have to be wired differently with the power transistors and an extra resistor. dam work is getting in the way of having a good fiddle with this project.
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Re: your own ignition

Post by minetymenace »

How about a circuit stew79, its hard to see what you are doing from the photos....
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Re: your own ignition

Post by stew79 »

hi minetymenace, there is a diagrame of the circuit on page 1 but the earth wire (bottom sketch) should go up from the power in at the bottom to the top of the bridge rect negative, and not the ac terminal from the transformer. the small hv cap across the dc out put is just to stabilize the voltage so the ac, tvc,s can send a sig back to the bc338 to reduce switching of tip 36c .it will be let in when its joined up to the main cap and fiering part of the ig (basic regulator as i think the out put must have the potential to make more voltage than is needed so as demand increases with speed the voltage wont drop off) also ,your high frequency inverters with only one power coil ,i cant see it being very good. the magnetic field in the core cant have enough time to decay away until the next pulse ? wont it just become a magnet ? to overcome this magnetic lag isnt that why they are normally push pull jobs with two identical primary coils, working against each other at the high frequency ?
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Re: your own ignition

Post by minetymenace »

How about a circuit stew79, its hard to see what you are doing from your description....
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Re: your own ignition

Post by Mark Cook »

I am enjoying this. The company who claimed to had invented the inverter driven CDI ignition system used a toroid transformer and a push pull oscillator. So much spark energy it could kill someone. They tried it on F1 cars in the 60's, but had trouble with plug leads talking to each other and causing misfires. You can have too much!
This design was stolen by a few companies. Even ended up being a basis for early interspan.
I was given the rights to the original design some years ago, but upset them by showing them a paper from earlier proposing their system.
Just goes to show, it's very hard to find the poor sod that does all the work and gets no credit. I doubt if any of histories inventers really did the donkey work.

Now if I could capture Gerry for a uninterrupted week, we could knock up something interesting that would suit every ones needs. A free week I suspect will be harder to get :cry:
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Re: your own ignition

Post by beat »

hi stew,
if I got your doing corectly, it will suffer on the problem of " not getting a stable voltage" in the 1 ( ore 2 ) uF capacitor.
if I am right, I was at this stage when oscillating the switch ( transistor ) for the coil with a NE 555.
ingoing 12V ( + 4 V, - 4 V ), outgoing 250 ore 600 , depending on the windings.

BUT, - when the unit was staying alone, - no spark producing, - the voltage rises up to nowhere, say 1200 Volts and more!!!
so each 800 Volt cap ore what ever bangs ! ( resistors in line just consumes, didn't help really )

the LM2587 is IMO a good way to go, - yes, the 5 legs needing the right place to go, other ways he will scuttle away........

beat :mrgreen:

minety, I guess I am winding my Travos wrong way round somehow,- I will make a new one and will come with pictures step by step .....

beat :oops: :oops: :oops:
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Re: your own ignition

Post by stew79 »

hi beat, i dont really understand "no stable voltage" ? i have a stable voltage, regulated with the tvs,s , and the size of the main cap isnt a problem? if the transformer is the correct size, its frequency of switching should increase as its out put demand is increased. (i think) i havent ever used a 555 thing as they dont fit in to my old fashion mind. as for transformers, round ones might be better than the old square ones i have been playing with. but any way i have re wired one of them with less on the feed back coil (10 t ) and joined that to one leg of the power coil (more conventional set up with an extra resistor between the base and earth.) this has been on the test rig on a 12 volt supply and works very well. it only draws 1 amp which rises to 1.5 at 12000 rpm. on the scope from the plug i can see the spark power drop of at high speed (when i was trying to make the ignition for the ccm i didnt have this ability, so used the spark length to see how much the power would drop at speed and adjusted the oscillator coils and transistor until i got the best results i could) as the square transformer wants to stay at a certain frequency, i think it is fighting against the feed back coil at higher speeds, causing the tip 36c to get warm (after 5 minuets at 7000 rpm) it was only about 50 deg with no heat sink but this is not a good sign. i have some 30mm pots from the ccm project left over so when i can i will wind some of those up with different ratios of turns and have another play
stew
ps i dont really need to do this playing around as the home made system i have on the ccm starts sparking from just 110 rpm and performs perfectly well from the old 2 pole stator and 2 pole rotor. i blame that "beat" for wanting a 12 volt battery set up and getting me interested again in all this head scratching !
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Re: your own ignition

Post by hwan »

Determined not to comment further on home made ignitions - i came across some dyno figures - published by a well known tuner - on big block, high compression hemi's (V8car engine) - you know, the ones with the s**t combustion chamber shape like a B50.

The MAX torque improvement, between points operated Chrysler ignition (in good order) and state of the art multi-spark MSD ignition and a Plasma add-on - was 3-4%.
Better engine designs show a much smaller improvement.

So - lets call it 5% improvement, so i can do it without a calculator, this = 1.75 BHP on a 35 bhp motor .............. not a lot.

This thread reminds me of the work done by G. Tesla - back in the early 1900's - we was trying to transmit power through space (inspired no doubt by lightning) - lots and lots of patents, some useful, but eventuality dying due to a head-attack - caused by HV electric !!!!
In fact if you look up his circuits, many of them have written LARGE on them - dangerous high voltages can kill (well high power levels can, anyway).

So why bother ..... get out there and ride the damn things ...
I'll shut up now ................. >44
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Re: your own ignition

Post by stew79 »

hi hwan, its good your back on this little topic as discussion and debate is always useful, it dosent matter that people dont agree with each other, i will always listen to others views and try to see if there is something i have missed. (the always learning mind) i have run many small scramblers and go-karts with 4 stroke bike engines, with points. if you try an use a smaller than std battery (just to fit it in out of the way) the engine will suffer at high speed . with a basic charging system the battery will over heat or the engine will still miss. you need that big heavy battery with its correct charging system. the first 125 H*nda i made a complete cdi for was tuned up as far was possible with point and a big battery. when i got the cdi working well i could advance the timing more and increase the jetting (0.4mm pilot to 0.5mm, 1.00mm main to 1.15mm) the cdi spark (which keeps its power even at higher speeds) meant this little bike (the engine was in a cr80 rolling chassis) would fly through the gears and rev to destruction if you let it. (the total system was less than half the weight of the points set up) when the next world championship speedway winning bikes ignition, is powered by a 60 amp hour battery with points or even an mdi system, i will look again at whether there is something i have missed.
stew
ps stay in touch, dont shut up ! if i wasnt working on a sunday i would be out there riding something !
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Re: your own ignition

Post by stew79 »

found an old pic of the little bike (was registered and on the road ! the kids thought that was great !) if it had ever gone on a dyno with the battery and points set up, to get a figure, then with cdi (and no other changes) the power out put would probably been the same. you can only get so much power out of a weekish (normal points set up) type of spark. cdi can take you further.
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Re: your own ignition

Post by HPbyStan »

IMO, contact breaker points would be a liability in a V12 Formula One car but are a good system on a 4 stroke single.
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Re: your own ignition

Post by beat »

HPbyStan wrote:IMO, contact breaker points would be a liability in a V12 Formula One car but are a good system on a 4 stroke single.
very , very true IMO.
stew79 wrote: if it had ever gone on a dyno with the battery and points set up, to get a figure, then with cdi (and no other changes) the power out put would probably been the same.
repetes the same, - very very true IMO.

BUT GENTS:

beat is NOT trying to build a CDI on its own style to get more power out of the engine, NO, - he dos this because :

IN THE STARTING PHASE, especially when used a electric starter motor, there is a significant drop in Voltage of the onboard system.

in this moment, a CDI is consuming around 3 Amps FOR A FRICTION OF A SECOND ( maybe 4 ore 5 m sec. ?) in compare to a Standard BSA points setup ( inductive ) wich consumes 3 Amperes all the time whilst the points are closed !!

And : the inductive used coil ( ordenary BSA ore car coil ) needs at least wheilst 40 ms this 3 Amps to build up the magnetic field where the spark duration of 4 ms can result :!:

so, as we have seen in above, the MINUS of a CDI is the short time of spark duration in starting phase, I try to build up a CDI where this phase is prolonged to the double at least, say 0.2 ore 0.4 ms.

and this hanges strongly together with the capacitor of 1uF ore 2 ore 3 uF and the voltage this caps are storing.

now the voltage is limited to somewhere 300 ore 400 V, the capacity is NOT limited so far, just put two ore more in parallel!
but it needs a MACHINE that can suply this enormous energy in this short time of 4 to 5 ms !

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Re: your own ignition

Post by hwan »

Mechanical Engineers (with some practical experience) - if it ain't broke - don't fix it.

Electrical/Software Engineers - if it ain't broke - its not got enough features and options yet ......

I'm not allowed to comment on Mechanical engineering anymore after AndyChaos' burned my degree after the 'fork-off' affair ....

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Re: your own ignition

Post by stew79 »

hi beat, done a bit more research on the 12 volt ignition, a tip36c seams the best trans, maintains max power till 6300 rpm then only drops of by 10 volts (on the scope) till 12000 rpm. thats a loss of only 100 ma in spark power (starting with 350 ma) this could be improved by reducing the number of turns on the secondary to 275. the max current the system draws is 1.2 amps, at rest (no sparks) it only draws 170 ma, the lowest voltage it will run from is 5 the max is probably over 20. find attached some pics of it (i will have to take the mjl21193 trans off and re place it with the tip36c as the resistors arnt right for it)
stew
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Re: your own ignition

Post by beat »

hi stew,

your newest baby looks good as far as I can see, and your posted values are promising much!

the pot core travo in the muserements of D 36 mm ( it seams you are using ) is one I do elaborate with as well because IMO it comes near to what I guess will work.

Question:
stew79 wrote: max power till 6300 rpm
means this 6300 sparks a minute ore 6300 rev's on a 4 strocke flywheel ?

I stil have the problem of NOT anderstanding your Layout, means how all the parts are working together.
sorry for it, but there is so many way to do it, and each detail is so important to get it stable running , having a high efficiency and lasting for long.

also each detail need to be measured whilst running in the values of Volts and Amps to make sure it is NOT overloaded for HEAT by low supply system voltage same as for high supply system voltage.

hope beat is not to boring for you....

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Re: your own ignition

Post by minetymenace »

beat wrote:I stil have the problem of NOT anderstanding your Layout
An "as is" circuit might help?
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Re: your own ignition

Post by stew79 »

a little road map.
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Re: your own ignition

Post by beat »

EXCELLENT stew !!!

it will take some time for me to get trough, but this is very helpful :!:

I made a new baby in the paper today, - hope the next two days I will have it on the test board.

what do you mean to it ?, what dos minty read on it ?
a other way to get 400V DC maybe
a other way to get 400V DC maybe
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Re: your own ignition

Post by minetymenace »

beat, you still using that 2587? Can't see from your drawing. I thought you were going down the fly-back route, in which case you don't need the bridge rectifier, just a single HV diode pumping up the voltage on the cap. The voltage on the secondary side of your trafo will shoot up when the switcher turns off (not when it turns on), so you only need one diode. Just make sure your core doesn't saturate, if it does gap it and/or reduce the "on" time (not sure you can do that with a 2587, but you could with say your old 555 and driver).

Do you want your 400v isolated?

You might want to put a dummy load on the 400v side, should calm things down a bit and provide a discharge path for the energy on the caps when you switch off.
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Re: your own ignition

Post by stew79 »

hi beat, managed to have another play with pots and wire. 275 t on secondary brought the un regulated voltage down to1360 from 1400 same performance on the rig ? tried 250 t but with all the soldering, handling, un connecting and re connecting the tvc,s (to get the 2 voltage readings) etc, this has caused an over voltage to the bc338. these are a bit sensitive and when even slightly damaged they reduce the normal switching of the main transistor. (with out taking any voltage or current measurements from the out put, you can tell its wrong by the sound of the oscillator) this small trans could do with a 500 ohm? resistor to earth and the hv signal going through perhaps a 2k resistor. ( this crude way of regulation is similar to that of an american battery run timing strobe light from the late 60,s i saw a circuit diagram for it in a library book some years ago, but that dosent have any big spikes of inductance flying around to deal with) anyway perhaps my power supply is down a bit ? (the 12 volt battery has been sitting in a box for 5 months, so its now on charge) in the mean time i have wound up another pot with 19 t on the primary and 280 t on the secondary, will try this tomorrow if i can
stew
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Re: your own ignition

Post by beat »

hi stew,
your coil winding is very well organized ! ( mines is a wild jungle system , means all real handmade :oops: :oops: )

this 1400 ore 1360 are Volts, right ?

if I am right, this is what I mean by unstable Votage.
ore do I miss something ??

the difficulty on this project is ( ore ONE of the Difficultys ) to produce a study 400 V , no matter dos the ignition sparking ore not sparking!
this 400 V should be readable at the capacitore of 1 ore 2 ore 3 uF.

stable !! no matter is the engine running ore is bike and rider falling to the ground and ignition is still switched ON.

the voltage may drop let say by 10% when crank revs are higher than 6 000rpm's, - this would not worry me to much.....

hi minety,
yes, still using LM2587 T- 12, because the futures of soft start, transistors protection by current limit, under voltage lockout and thermal shutdown
plus others are reasons to keep on it....
minetymenace wrote: Just make sure your core doesn't saturate, if it does gap it
yes, I do work with different cores , gapped ones and ungapped ones....
minetymenace wrote:reduce the "on" time
no chance for this on the LM 2587, <218
minetymenace wrote:put a dummy load on the 400v side, should calm things down a bit and provide a discharge path for the energy on the caps when you switch off.
good Idea, - I will see for what I do find in my R box..( it may protect from changing hair style.....) :lol:

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Re: your own ignition

Post by stew79 »

hi beat, i thought you got the technical stuff ? (looking back at your other post on ignitions?) do you know what a tvs is ? i take 2 readings for an experimental coil thing, one un regulated (to see what its max potential is) and another regulated reading to see what current it draws when not sparking (turned on but "engine" not running) from these figures i can see how changes to the wire thickness, number of turns, transistor resistor etc effects that part of the performance. then its run at different speeds on the test rig, recording its input current (with a digital meter as the round ammeter with the battery isnt accurate enough) with the rpm meter i record the speed that the spark current drops off and by how much. the max frequency of the oscillator means that over a certain spark speed the charge up time for the main cap isnt enough, and it will reduce in power. this is expected, and the major limiting factor with indirect or battery powered ignition. its not a problem as long as at 8000 rpm there is still enough for a good spark. with a more sophisticated, and complicated power supply you can run much faster but thats not necessary here. (this is similar to when i sorted out the ccm ignition afew years ago, but then i was making an alternator as well and trying different coil combinations on that, with the ignition as well !!!) back to the regulator, dose your 5 legged pet have one ? will it draw the same current at stand still, as flat out ? as for size of capacitor, you seam to think that the size effects how long the spark lasts ? have you ever analyzed a spark on a scope ? you will be surprised at what really happens !
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Re: your own ignition

Post by Ian Hingley »

beat wrote:...ore is bike and rider falling to the ground and ignition is still switched ON.
You're so thoughtful beat - thinking of people like me even at the design stage! <216 <216 :thumb

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Re: your own ignition

Post by stew79 »

calling beat... come in beat....beat do you read me..... over..... beat ?? beat where are you....... anyway i got fed up with swapping resistors over and probably putting the wrong values in so i found up 2 rheostats of suitable wattage and ohms, and fixed them to the test plank (cant really call it a board) now i can fine adjust the values with it running on the test rig to find the best settings. the 2 stats can be un plugged from there circuits so a reading can be taken of there present resistances ! (i should have put them on there from the start ?) had a quick run and all is looking much better. the hv from the tvs is going through a 2k res and that also seams to be better. here are some more pic.
stew
ps to hawn if hes listening. i found up that article from the 70,s cycle mag about the racing beemer, by the world famous "butler and smith" engineers, tuners, and innovators. (who have there own workshops and a dyno) i remembered some of the stuff a bit wrong (it was from years ago) but with 2 plugs in each head of the beemer, they also "DRASTICALLY" reduced the timing ......... by a whole ....TWO.... degrees !!!!!!! this gave them no extra power. however the sparks came from a Bosch cdi system, so with such a strong spark in the first place it underlines how important cdi can be in a proper race engine.
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Re: your own ignition

Post by beat »

hi stew,
stew79 wrote: do you know what a tvs is ?
google says :Television set.
no, I do not have one.
stew79 wrote:dose your 5 legged pet have one ? will it draw the same current at stand still, as flat out ?
yes, the LM 2587 T 12 dos regulate the current to keep the HT voltage
( Ht means in this case the 400 ore what ever is set by the Turns and the two Resistores near the feedback. )
stew79 wrote:as for size of capacitor, you seam to think that the size effects how long the spark lasts ?
Yes and No.
the discharging time of a Cap is given by the stored energy ( Volts and Capacity ) and the Resistance in the discharging line.
Shure is: Voltage around 400, Capacity 1uF , Resistance 0.5 Ohm in the primary of a real CDI Ht Coil = spark duration of 0.2 ms.
so, the safest way to improve this is MORE CAPACITY. NOT higher Voltage nor greater Resistance. IMO.
stew79 wrote: have you ever analyzed a spark on a scope ? you will be surprised at what really happens !
yes , I do have a scope where I can measure the Voltage in the HT lead near the spark plug.
but this dos not say so much, - and a real Spark Analyser working by the light spectrum is far away for my pocket, so I know just the things from reading what others are saying about the three steps a spark is doing about energy and time.

Hmmm stew,
you also realize : as further we get in to it as more questions are coming up!! :lol:

and always, always it needs to make a compromise. - what are you looking for, how long you will put time and effort in to get it as near as possible to your target.

beat <216

Ian Hingley wrote: - thinking of people like me even at the design stage!
:thumb :laugh :laugh
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Re: your own ignition

Post by stew79 »

hi beat, i have read back through all this topic to see if i have missed out on any detail. i think its alright so things must be getting lost in translation. a tvs is a "transient voltage suppressor" the ac versions i like, are like 2 zeners back to back. at there rated voltage they conduct (wide tolerance so they have to be individually tested) they are for clipping an over voltage to earth, but are just as useful in sending a signal to the small regulating trans to keep the power supply at your chosen voltage. here is a drawing of one way to look at a spark on a scope (from "the boffin of oz") fiddle with the ranges to see it or look back to one of my earlier pictures of a spark and see how the scope was set. all will become clear.
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Re: your own ignition

Post by beat »

hi stew,
stew79 wrote:transient voltage suppressor"
tvs, I got it now = supresserdiode in german.
usuable safety device, - it should not be in continues work I say....
stew79 wrote: but are just as useful in sending a signal to the small regulating trans to keep the power supply at your chosen voltage.
by studying your roadmap, I was guessing you are doing something like with your BC 338, - but this road is to unsafe for me.
in oposite to your use of the bike, - mine has to go save in the 3rth lane of the freeway in to Zurich ore Bern whilst rush hours, a failure in ignition may make me flat like a carpet and let me look like a skin of a bear in front of the chimney !

so, the way of reducing Amps to keep the Voltage in balance is the way to go I guess, this LM thing looks good IMO.
stew79 wrote:here is a drawing of one way to look at a spark on a scope
thanks stew, I will come agayn to the stage of measuring spark when chapter ONE : producing stable 400 Volts in a capacity of 2 ore evan 4 uF is reached.
and this 400 V must be reached by 80 ore 100Hz of discharging the Capacity !

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Re: your own ignition

Post by stew79 »

hi beat, had any luck with your 5 legged friend ? had a play with your scope looking at sparks ? i have done some more winding and experimenting with 30mm round pots, and got a better rheostat for testing, (once a setting is selected the stats are replaced with resistors of that value, although running through the stats has no effect on performance?) tried 2 tip36c,s in parallel with lower turns on the primary, and the higher rated mjl21193 trans with all combinations as well. there seams to be a ceiling for performance with the round pots ? one of my old square transformers, with out any fiddling with different value resistors, number of turns etc (with a tip36c) will out perform all the 30 dia pot in all the ways i can measure ? i will run the square one again soon with the rheostats to find its peek performance, and best number of turns etc for a 12 volt supply. (thats lowest m/a at res, lowest start voltage from 6 up, highest speed with full spark power, smallest drop off at 10000rpm, and lowest max speed amps draw) i am sure a reliable, low power consumption, simple, cdi from a 12 volt battery or normal battery and generator system is very close.
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Re: your own ignition

Post by beat »

stew79 wrote: had any luck with your 5 legged friend ? had a play with your scope looking at sparks ?
not yet stew, - was a few days in the alps for snowboarding :cool:

interesting your Transformator testings.

do you use any ferrits with a air-gap ore are they all witouth gap ?
theoreticaly, the gap will bring the higher performance, - if I am right -, but it hanges together with the amounth of uF of capacitors should be filled....

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Re: your own ignition

Post by minetymenace »

You must have a gap, or use a gapped core material, otherwise it will saturate.
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Re: your own ignition

Post by stew79 »

hi beat, lucky bugger having a holiday in the snow ! (not at all jealous) as for transformers, they are all normal ferrite ones with no gap (never had any with an air gap ? isnt that just for very high frequencies ?) the simple 12 volt set up i am working on (just for fun) is nothing new and clever, or high frequency. its just because i have most of the parts already from my last big experiment (ccm) and when you said you wanted a 12 volt thing i thought i would give it a go. using the rheostats with other instruments has made it so much clearer about how this old fashion type of oscillator works, and can be made to do different things. if the output is too "powerful" it will latch the firing thyristor and stall the ignition. it must be capable of withstanding a short, and stalling the oscillator, to allow the thyristor to re gain control. the number of turns on the feed back coil is very important for how much power is needed to run it. the ratio of the 2 main resistors is approx 1:10 and with all the parts of the recipe coming together well it wount be long before any one who wants to have a go at making one for them self' will be able to. the cost of all the parts is £30 (approx, the coil wire is the most expensive as you have to buy the small reels) work is getting in the way of this project but soon it will be over.
stew
ps how dose the size of cap effect the oscillator ? within the range of 0.47uf to 2uf ? it just takes longer to charge a bigger one to the same voltage.
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Re: your own ignition

Post by stew79 »

hi minetymenace, i dont understand the saturated thing ? thats what i thing will happen to the 100khz coil without a push and pull driver ? (not enough time to recover)
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Re: your own ignition

Post by minetymenace »

Saturation is what happens when you pass so much current through a coil that the magnetic circuit is full of flux, and it stops acting like a coil and becomes a low value resistor. If this happens your switching device will be switching more and more current but with no increase in stored energy in the coil.

By gapping the core, it increases the "resistance to the magnetic flux" (as it were), so it takes longer for the flux to build and reduces the chances of saturation.

beat's five legged fuse has a soft start, which will prevent the peaks of current at the start of the charge, at work we dont drive the switching device with a square wave, but have a short high pulse followed by a longer gap, so by varying the mark/space ratio we can prevent saturation.
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Re: your own ignition

Post by beat »

hi stew,

if I got it right, : as higher the frequency, as less the tendencies to saturate.
but this is only one point, - the ON time in relation to the OFF time dos a lot as minety says.
same as ferrite material, gap, type of transformator.
when I laborated with the NE555 where this signal was easy to modulate, the effect was amacing.
unlucky the LM2587 ( with 100 khz ) dos not offer this, but a couple of other helpful futures....
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Re: your own ignition

Post by minetymenace »

I'm with you beat. your device does have current limit, which will stop the switcher being destroyed if it does saturate.
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Re: your own ignition

Post by stew79 »

hi all, this saturation thing beyond my understanding. i think it only apply,s to the 5 legged world of very high frequencies. as i am only in the old fashion world of just audible frequencies, and transistors it cant happen. i can have a state when the main trans hasnt got enough base to turn on, or the feed back pulse isnt powerful enough to turn it off, but thats nothing to do with saturation. if i was better with a scope i could look at the signal from my feed back coil to the main transistor, and adjust the 2 stats to get the best balance. thats the current to switch the trans on,(one resistance) and the induced current back from the feed back coil to turn it off.(thats the other resistance, classic Hartley Oscillator) i have got a spare scope with only one working channel (volts div control knob broken half way down in side) so this could be used to measure the spark energy, and the better 2 channel scope to look at how the trans is switching. the part i would struggle with is knowing what to look for on the screen. just going by how it sounds and the spark energy verses the input current will have to do. i have refined one of the old big square transformers and can run it on the rig at 10000 rpm for 5 mins with all of its components staying cold !!. i am struggling to get the same efficiency from any of the smaller round pots, its the old electrical proverb that says "with size come efficiency". tomorrow if i can i will try running a modified version of the alternator system thats on the ccm from a 12 volt supply, for cross reference purpose only. this uses the higher rated mjl21193 trans with a small snubber network across the emitter and base. (with much higher value balance resistors, still in the ratio of 1;10)
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Re: your own ignition

Post by minetymenace »

stew79 wrote:it only apply,s to the 5 legged world of very high frequencies.
au contraire mon ami

But your circuit and beats operate on different principles.
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Re: your own ignition

Post by beat »

thanks minety,

stew, I am on to make a droing from your roadmap from " left to right ".
just as I can better understanding it, - your way is interesting, evan if I feel as it will not be the way for me.

guess it is ready tomorrow.....

beat.

and as mark cook says somewhere: wiggeling faster is the way, - and controlling the Amps, the minimum Voltage, the heat and the over Amps, - what we want more ??

beat ( if it works.... :oops: )
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Re: your own ignition

Post by beat »

hi stew,
as far as I can read / copy it....
as far as I can read / copy it....
did I got it right :?:

beat
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