This is it !

[sucahyo]

nice progress everyone .

Farmhand, thanks for voltage info. Do you ever try to use desulfator from the solar panel to battery? Or panel voltage is a problem? Maybe joule thief?

[Farmhand]

Suns out and the internet is fixed. and my floors are dry again. I am one of the lucky one's lots of homeless here now.

nice progress everyone .

Farmhand, thanks for voltage info. Do you ever try to use desulfator from the solar panel to battery? Or panel voltage is a problem? Maybe joule thief?

sucahyo, Not yet i'm working on solving the fluctuating voltage problem, I don't have one that can take 3.5 amps yet but i'm working on that too.

Now on can concentrate on what i'm doing. All the drama is over for me.

Cheers

[sucahyo]

Suns out and the internet is fixed. and my floors are dry again. I am one of the lucky one's lots of homeless here now.



sucahyo, Not yet i'm working on solving the fluctuating voltage problem, I don't have one that can take 3.5 amps yet but i'm working on that too.

Now on can concentrate on what i'm doing. All the drama is over for me.

Cheers

Good news . Can't you just parallel some MOSFET to the desulfator circuit? Isn't your current desulfator can already take that amount of current?

or maybe variable voltage output of solar panel can fry the timer chip?

[Farmhand]

Good news . Can't you just parallel some MOSFET to the desulfator circuit? Isn't your current desulfator can already take that amount of current?

or maybe variable voltage output of solar panel can fry the timer chip?
Today 06:41 PM

Yeah can almost take that with two fets but I need to regulate the voltage to the pulse generator to under 15 volts, and I have never used a voltage regulator, i've got one, fixed 12 volts, just haven't got around to it yet.

But I will do it sooner or later. Too much current will saturate the little cores too. It takes about an amp to warm them up though if I wind them different they could take more i guess. Thicker wire maybe too, I have a couple from a UPS with really thick wire I think they are rated to 2 amps each, they might work.

Cheers.

P.S. Just watched your vid 7imix good job you got some fairly busy up and down spikeing goin on there. I was going to try something similar to that out of curiosity, interesting, don't dismantle the ghetto coil without more experiments if you can help it.

[7imix]

I made another video of pulsing the ghetto coil. I also added three smaller coils in between the coils I already had. I want to make a better video but in the meantime check this one out.

YouTube - Ghetto coil 2

[gmeast]

Ghetto coil 2

I made another video of pulsing the ghetto coil. I also added three smaller coils in between the coils I already had. I want to make a better video but in the meantime check this one out.

YouTube - Ghetto coil 2

Very COOL! It seems you are seeing the same thing I have seen in my circuit. The MOSFET gate needs to be driven 'solidly' with a 'real' gate driver circuit ... I posted a generic version. Famhand did or will too. When you hooked up the power to the MOSFET, you saw a change in the gate waveform, and that is simply an unstable charge on the gate. The mosfet is 'pulling' the gate charge around. You may also be seeing an oscillation and maybe a harmonic and the gate is reflecting the drain, and the drain is reflecting the gate. That should clear up with better gate driving gear. You also saw spikes above battery+ but also a -dimple below battery+ (leading the +spike). That I'm sure is associated with a 'squishy' gate charge and will go away later leaving a small +, flat bump which IS the 'real' charge going above battery+.

Nice neat job and I get a kick out of the name you've given your hardware ... "Ghetto Coil" ... that's great!

Later all

[Farmhand]

Good job 7imix, I like it, you do very neat work. Looking at that across the battery scope shot is very promising. We just need to straighten up the gate drive signal and you will be able to reduce the pulse width a bit more without loosing amplitude on the signal. There appears to be a few viable ways to do that, trying to find which will be best for the paticular circuit arrangement we end up using will be a trial and error deal to an extent, it's hard to know untill it's tried.

I still have not been able to relieve myself of distraction long enough to try this-
http://public.bay.livefilestore.com/...ter.jpg?psid=1

I think Cb can be done away with, aswell as the zener if we use regular MOSFETs with 12v. That will make the gate charge fully and quick to get the lowest "on" resistance and most importantly the pnp transistor will ground the gate charge pronto, to switch the fet off fully as quick as is possible. I think something similar to this or even this type of gate driver will be the best. I don't know a great deal about the op-amps and stuff but they all do a similar thing.

Although I said about three days ago I was going to try drivers and the op-amp circuit I have failed to do that yet, due to my skittish mind more than anything.

If I make a drawing incorperating the op-amp with the gate driver above, I will run it by Gmeast to see if it is viable first might be easier, maybe you could then try it with you solderless board. Your scope has actual measurement abilities. Very usefull.

Anyway I'll try to make a drawing first.

Actually if you want to try something quickly since you already have a working circuit, just remove the 100 ohm resistor from PWM to gate and the 1kohm from gate to ground, then place a 1n4148 diode from PWM to gate, take a small pnp transistor and connect the base to the anode of the 1n4148, the collector to the gate and the emitter to ground. When the PWM puts out a pulse the transistor will stop cunducting to ground allowing the gate to charge and when the pulse is over it will conduct the gate charge to ground very quickly, try to adjust pulse width and frequency down to low power draw first before energising the circuit, just incase. That should hopefully straighten things a little, not the best way but effective and simple.

Make sure if you use a TO 92 package to check the pinout configuration on the datasheet MPSA56 is 1 emitter 2 base 3 collector.

Cheers

Edit Gmeast if you look back to post 115 page four, I think you hit all the nails right on the head way back then, free running oscillators would be easy and may well produce the best result for this particular application . It would be difficult to know though without trying some other techniques. If he was pulsing the coils in a constantly changing pattern like ,123,121,123,121 as Pmazz indicated he might be, on page three. Wouldn't that set up an repeating interference pattern creating several harmonics ? maybe someone already mentioned that, probably you. But I can't find it.

[7imix]

Thanks guys. Looking forward to trying a better MOSFET driver. Thanks farmhand for the instructions. I'll mess around with it a bit, hopefully later today.

Happy new year! 2011 is going to be great.

[Farmhand]

Yes Happy New Year everyone.

I forgot to mention using the 10 volts you are should be fine, good for testing how well the gate driver works. You could also put the 100 ohm resistor on the base of the transistor but it's not really needed with very narrow pulses, might heat up a bit if the duty goes way up. Maybe thats part of my twitching trace problem, when I first energised my cicuit I had the frequency and width maxed out, it might of heated up the transistor base and damaged the tranny, i'll try replacing it. I had it adjusted backwards of course. No matter how I try I always get something backwards. Now I go by actual resistance rather than the way I screw the pot, depending on which pins you use on the trim pot decide's which way is what. I hope that made sense.

Anyway almost 2 AM, it's the 2nd January here. I missed the countdown to the new year because I had my face about 6 inch's from my computer screen looking at Tesla drawings. Sad I know, but don't feel sorry for me. Hahahah, I love it. Time to make drawings, I have about 4 and a 1/2 hours till the sun comes up. I missed it so bad when it was raining. I start to feel sick with no sunlight for so long. Someone told me we get vitamin E or D or something like that from the sunlight. Wow.

Cheers

[Farmhand]

I think I will try this but without the 5.6 v zener which i think is for use with logic level devices. Maybe a resistor will be needed where the arrow is pointing, not sure. If the supply is much over 15 maybe an 11 or 12 volt zener instead of the 5.6 volt one, just to make sure the fet gate is not hit with too high a voltage, the gate resistance of a mosfet is effectively infinate and with such narrow pulses the current to it wouldn't be much, I've been told mosfets are prone to static damage, maybe thats because of the field effect thing. A driver like this should provide a good crisp and full gate charge, i'm just not sure if all the transistors will make it too slow. I'm guessing with these transistors an actual switch time of about 1 usec would be the fastest possible. .

Also if you put a 100 uf or so cap across the PWM supply points and a few hundred across the power rails near the coil that might smooth things out a bit too. Worth a try, if you have some I use 100 and 470uf. Caps are leaky I know, I've never actually been told the function of those caps but I surmise that without them the current draw of the coil could interfere with the smooth and precise operation of the pulse generator and the pulse to the gate.

Rgds

[Farmhand]

Having looked at that drawing for a while I can see that maybe a resistor is needed above the single transistor to bias the resistance towards the pair of transistors especially if a resistor is used where the arrow is pointing. Thats also above the connection to the pair of bases to the single transistors collector.

I guess we could try it as in the original drawing, about four posts up, but without the mystery value cap, and zener then just remove whatever else is not necessary. Less is always better.

Unless it's cake of course.

Edit changed part of post, sorry.

[cikljamas]

Guys, we have to switch this thread to croatian language
If i am absent one day than i have a lot of words to read through and
it is not so simple in any other language but your native tongue, believe me,
especially if you are not expert in the field which is the subject matter of the
discussion !
But, i already used to the fact that british empire conquered half of the world
instead of croatian empire despite knowing that once upon a time Napoleon
said after one battle during withdraw from Russia (croatian soldiers protected
one bridge and most of them got killed by russians but saved the french army),so Napoleon said after that event : give me 100 000 croatians and i am gonna conquer the whole world ! Did you know that few hundred years ago there was the same number of english and croatian habitants, and now there is just about 5 millions croatians and about 100 millions of englishmans ! What that tells you ? So much wars here through history, so much mass destructions...
So i mentioned this like a joke, but who knows, if history was just a little bit
different now we could talk croatian...
Anyway, i am proud of YOU and your deeds and not just on behalf of that :

HAPPY NEW YEAR TO ALL OF YOU !!!

[gmeast]

driver

Hi all,

On this gate driver thing ... now I don't know what to think. I have been looking at the schematic for the Boyce's PWM3F (earlier rev) I guess that's what it's called and its simpler. It uses an Opto-Coupler that has an internal amplifier (going by the part number).

Here's the schematic for the 3F:
http://02d1852.netsolhost.com/radian...g/PWM3fshc.pdf

Here's a picture of the PWM3G (current rev):
http://02d1852.netsolhost.com/radian...pwmg3_1008.jpg

Now note in the schematic there is no complex gate driver other than the 'logic output' Opto-Coupler ... PCP116-TR.

BUT ... this is a six-pin through-hole device by the description at Digikey and yet every photo, including those views visible on the video if the Hex Controller show an 8-pin through-hole device. So, "What's up with that?"

Anyway, everyone peek at the schematic and absorb it a little if you don't already have it downloaded. The state of disclosure is here is lacking even though they released it to the public. I'd like to see a '3G" schematic, but they are not publishing it. If the 3G board photos are actually of the 3G board than you can see every trace in those photos.

Happy New Year

correction:OCP116-TR is the DIP package but still six pin device PCP116-TR is SM OK so that's wrong too ... does anyone know?

[Farmhand]

Oh my goodness, do I see 19 capacitors and 2 voltage reguators on that board ? The timer chips are NE 556, not the best. Two different voltages 12v and 8v I see two negative inputs and the three recovery output diodes but I dont see where to connect the three coil negatives. The way i see it one of the two negative inputs on the left take the three coil negatives paralelled, the other negative and the positive on the left terminal block are supply. I don't see the point to three mosfets unless the three coils are switched by one fet each.

I would like to see a scope shot of the gate charge pulse. I don't understand how the fall time can be crisp enough without the gate charge being grounded away. Bob does say somewhere that the earlier boards are only proof of concept and don't perform anywhere near as good as the Hex controller board. The 1k resistor on the gates should only be necessary because the gate charge is not grounded away and must be dissapated by the resistor, I think, maybe i'm missing something. The IRF540Z's are automotive mosfets. Probably worth a pretty penny.

Rgrds

[gmeast]

on the photo:

Oh my goodness, do I see 19 capacitors and 2 voltage reguators on that board ? The timer chips are NE 556, not the best. Two different voltages 12v and 8v I see two negative inputs and the three recovery output diodes but I dont see where to connect the three coil negatives. The way i see it one of the two negative inputs on the left take the three coil negatives paralelled, the other negative and the positive on the left terminal block are supply. I don't see the point to three mosfets unless the three coils are switched by one fet each.

I would like to see a scope shot of the gate charge pulse. I don't understand how the fall time can be crisp enough without the gate charge being grounded away. Bob does say somewhere that the earlier boards are only proof of concept and don't perform anywhere near as good as the Hex controller board. The 1k resistor on the gates should only be necessary because the gate charge is not grounded away and must be dissapated by the resistor, I think, maybe i'm missing something. The IRF540Z's are automotive mosfets. Probably worth a pretty penny.

Rgrds

The output bus for the 3 coils are on the right side of the photo (blue header). I have the same Q? about the gate drive, but remember, everything in that area, (the LED, transistor (phototransistor) are part of the opto-coupler...so the apparent grounding may be all it really is). Anyway, I don't think the schematic belongs to that board (exactly). The board is the "G" rev and the schematic is the "F" rev.

Anyway, I didn't know if you guys had seen these. I had figured you guys would have already downloaded this stuff.

Happy New Year