Stingo Solid State Battery Charger

[Godfrey]

Hi Sucahyo,

In an earlier thread on Imhotep’s car relay battery charger, you started sharing details about your Stingo battery charger circuit. I’m now working on a replication and would be grateful if you could answer some questions about it.

Here are some schematics I’ve put together for my own understanding:



The second circuit is a test configuration. If everything’s working, it should light the neon, right? Please let me know if you see anything amiss.

I’m actually using a 1M potentiometer instead of 500k, because that’s what I’ve got on hand. The resistors and potentiometers are all rated for ¼ watt, and my capacitor is actually rated for 250v.

If it’s all about generating and collecting the maximum back EMF, the secondary of the car ignition coil is not used, right?

What is the working source battery voltage range for driving a typical car ignition coil?

What is the frequency range? I remember you said it can get very high. What’s appropriate for this type of coil?

It’s a type of complimentary multivibrator that I’m not familiar with. Can you describe its two states? I’m confused in particular as to how the emitter of the PNP transistor feeds the base of the NPN one. It would make more sense to me if it were the collector instead.

What exactly does the capacitor do? Is it a low frequency filter? Won’t it give the output wave a sinusoidal shape?

For charging smaller batteries, it would need a different coil that could be driven on smaller voltages than 12V, right?

Thanks ahead for your help.

- Godfrey

[sucahyo]

The second circuit is a test configuration. If everything’s working, it should light the neon, right? Please let me know if you see anything amiss.

It suppose to lit but you don't need capacitor. You have to put atleast a diode if you intend to charge battery.

I’m actually using a 1M potentiometer instead of 500k, because that’s what I’ve got on hand. The resistors and potentiometers are all rated for ¼ watt, and my capacitor is actually rated for 250v.

My capacitor is rated for 250V too.

If it’s all about generating and collecting the maximum back EMF, the secondary of the car ignition coil is not used, right?

Yes. I wound my coil without secondary. For safe operation, short the secondary.

What is the working source battery voltage range for driving a typical car ignition coil?

From 3V to 24V, what ever you have and what ever output you need.

What is the frequency range? I remember you said it can get very high. What’s appropriate for this type of coil?

Above audible range down to 50Hz depend on load, coil and resistor value.

It’s a type of complimentary multivibrator that I’m not familiar with. Can you describe its two states? I’m confused in particular as to how the emitter of the PNP transistor feeds the base of the NPN one. It would make more sense to me if it were the collector instead.

Sorry, I can't explain it either. I found it by accident. That is more efficient than using the PNP in a normal way. Harvey suggest an SCR to replace it but for me, TIP32C is more obtainable and cheaper.

What exactly does the capacitor do? Is it a low frequency filter? Won’t it give the output wave a sinusoidal shape?

To increase efficiency, to prevent too much normal electricity flowing to the load.

In my opinion, the spike is bouncing, so by using FWBR I get the weaker reverse bounce too and I use capacitor to prevent the load from getting powered by the source battery.

For charging smaller batteries, it would need a different coil that could be driven on smaller voltages than 12V, right?

I am using same circuit to charge any kind of battery between 1.5V to 12V. I don't think you can make 1.5V nicad overheat if you only use one stingo

[SeaMonkey]

Sorry, I can't explain it either. I found it by accident. That is more efficient than using the PNP in a normal way. Harvey suggest an SCR to replace it but for me, TIP32C is more obtainable and cheaper.

To increase efficiency, to prevent too much normal electricity flowing to the load.

The PNP Transistor is connected to operate in what
is known as "inverse mode." The Collector is functioning
as the Emitter and the Emitter is functioning as the
Collector.

By working in "inverse mode" it effectively reduces the
base drive to the NPN Switching Transistor thereby
preventing it from being overdriven.

The Current Gain (Beta) of a transistor in inverse mode
is approximately 10% of normal gain.

To attain the same effect with the PNP Transistor
in normal mode a variable resistor could be connected
in series with the NPN Base lead in order to "tune"
base drive for maximum efficiency.

There is nothing wrong with "inverse mode" operation.
It is seldom used but a good "trick" to remember when
it can be taken advantage of.

[7imix]

Godfrey, thanks for starting this thread, and sucahyo, thanks for discovering the stingo. :-)

The stingo is absolutely my favorite thing to experiment on, and I anticipate it will continue to be. I have had so much fun building a couple and experimenting with them. The stingo sparker is my favorite. I have tried replicating the modification with a brushed dc motor but I don't have exactly the right parts and it is not working as it should.

I have been performing some measurements with my little scope and my nice new high voltage probe. With the spark gap running I have measured up to about a megahertz. With no load I was able to get way up high above audible range, something like 25mhz. I will measure again and take more accurate notes.

I measured about 2000 volts off the high voltage side, which seems a bit low to me. I will go back and double check my measurements. Also, I measured about 800 volts with the probe just in the air, a few feet away from the apparatus! It diminishes as I move the probe radially outwards. I will take a movie of this. It's quite interesting.

I also did some experiments hooking up some capacitors and bars, hairpin style. I was able to get it to light a couple of neon bulbs. Will definitely do more experiments with this! Awesome.

I need to get my camera charged and take some video. I have lots of observations to share.

Thanks again sucahyo! Your circuit is great!

[sucahyo]

I have been performing some measurements with my little scope and my nice new high voltage probe. With the spark gap running I have measured up to about a megahertz. With no load I was able to get way up high above audible range, something like 25mhz. I will measure again and take more accurate notes.

That is very high. That is not a typo?

How many volts at low voltage side?

Thanks again sucahyo! Your circuit is great!

Thank you. I really glad if my circuit is usefull .

[7imix]

That is very high. That is not a typo?

You're right, it was a typo. I meant kHz.

How many volts at low voltage side?

I'll measure.

[Godfrey]

Hi All,

Thanks for your posts Sucahyo. I forgot to ask you about the knobs. What do the two potentiometers control. I assume one is for frequency, but not sure which.

Yes. I wound my coil without secondary.

You wind your own coil for your Stingo? Air core or ferrite? I’m using an eBay bought cheapo car ignition coil.

For safe operation, short the secondary.

Would it be better to short the HV output to the case rather than the negative terminal? I’ve noticed from continuity testing that they aren’t the same thing.

In my opinion, the spike is bouncing,

I agree. Coil ringing may be a factor too.

so by using FWBR I get the weaker reverse bounce too

Good idea to use FWBR!

and I use capacitor to prevent the load from getting powered by the source battery.

So the cap is a DC filter? What load are you talking about? The charging battery?

The PNP Transistor is connected to operate in what is known as "inverse mode." The Collector is functioning as the Emitter and the Emitter is functioning as the Collector…a good "trick" to remember when
it can be taken advantage of.

Thanks so much for that very helpful information, SeaMonkey!

I need to get my camera charged and take some video. I have lots of observations to share.

Thanks, 7imix - Great input! I’m looking forward to your video, scope shots and further measurements.

Above audible range…That is very high. That is not a typo?

Isn’t the top of the human audible range around 20kHz?

- Godfrey

[sucahyo]

Thanks for your posts Sucahyo. I forgot to ask you about the knobs. What do the two potentiometers control. I assume one is for frequency, but not sure which.

All potentiometer change frequency. But each have different most efficient position that change with the load. If you have two amp meter, you can know the position on spesific load.

You wind your own coil for your Stingo? Air core or ferrite? I’m using an eBay bought cheapo car ignition coil.

I wound it my self to make it small. Any coil can be used. My best is air core but what I use to charge battery is the small toroid one.

Would it be better to short the HV output to the case rather than the negative terminal? I’ve noticed from continuity testing that they aren’t the same thing.

I don't know. I suggest to short the HV output for safety. The output should reduce a bit but see if you get it too.

Notice that you can only get radiant output with shorted secondary with stingo. On any other radiant circuit you must let the HV output open to get radiant output.

So the cap is a DC filter? What load are you talking about? The charging battery?

Yes and yes.

Isn’t the top of the human audible range around 20kHz?

Yes. Sometime I can not hear it's whine. Usually when charging an empty battery.



BTW, as charger, I prefer multiple stingo combined with my FWBR combiner than single stingo. Efficiency of combined circuit: 1 + 1 > 2.

[7imix]

All potentiometer change frequency. But each have different most efficient position that change with the load. If you have two amp meter, you can know the position on spesific load.

Where do the meters go? When the meters are in place, is the goal to maximize current?

I wound it my self to make it small. Any coil can be used. My best is air core but what I use to charge battery is the small toroid one.

What is the diameter, how many turns, and what gauge wire for your best coil? I will make one. I wanted a smaller coil to make it easier to put in a project box.

[Ecoman11]

@sucahyo

Have you tried to connect the negative of the battery to the positive of the source? Disconnect the negative on the FWBR and connect it to the positive of the power source. See if you get an increase, decrease or same current for both draw/input.

Ecoman

[7imix]

If you are not watching this other thread yet, it's another stingo variant, and I made some progress reproducing it today, so check it out. There's a movie of some cool results.

http://www.energeticforum.com/renewa...tml#post111889

I also took some video of the stingo sparker and the stingo running with the high voltage side of the car coil shorted. It's uploading right now, I'll post a message when it's done processing.

[7imix]

Ok, here is the first of a series of videos showing measurements of one of my stingos.

YouTube - Stingo Spark Gap Measurements

The frequency range I was able to measure is about 800hz to 5.5khz.

With the gap the spike is a lot dirtier, with a lot of bounce after the initial spike. I may not be getting a DC spark. Perhaps my magnetic quencher is in the wrong orientation, or the magnets are not close enough. I will experiment some more.

In the next video I perform measurements with the high voltage side shorted instead of a gap, and the spikes are much cleaner.

[sucahyo]

Where do the meters go? When the meters are in place, is the goal to maximize current?

The goal is to maximize output current first, and then minimize the input current. But that is optional, you can also choose higher output instead of highest efficiency.

What is the diameter, how many turns, and what gauge wire for your best coil? I will make one. I wanted a smaller coil to make it easier to put in a project box.

For charger I use computer power supply toroid. As for the coil spec, I don't know, sorry:

Have you tried to connect the negative of the battery to the positive of the source? Disconnect the negative on the FWBR and connect it to the positive of the power source. See if you get an increase, decrease or same current for both draw/input.

FWBR in series with cap is what I get after some experiment. You will get 40%. You can add another 20% with a trick but I am still not sure if it will be good for the battery.

With the gap the spike is a lot dirtier, with a lot of bounce after the initial spike. I may not be getting a DC spark. Perhaps my magnetic quencher is in the wrong orientation, or the magnets are not close enough. I will experiment some more.

Try with water surface too or increase the input voltage to 24V or something.

Thanks for the video . I really love the spike reading . Show sign of h wave too .

Can you show scope reading with shorted secondary and your hand toucing the PNP base?

I see delta T as 300uS, for small or big grid? that means the spike width is around 50uS or something?

[7imix]

The goal is to maximize output current first, and then minimize the input current. But that is optional, you can also choose higher output instead of highest efficiency.

thanks, I am looking forward to trying this.

For charger I use computer power supply toroid. As for the coil spec, I don't know, sorry:

Ok, I will just wind a few coils and try them out. Thanks

Thanks for the video . I really love the spike reading . Show sign of h wave too .

Can you show scope reading with shorted secondary and your hand toucing the PNP base?

I see delta T as 300uS, for small or big grid? that means the spike width is around 50uS or something?

You are welcome. What is an h wave?

Here is the second video I made today, of the secondary shorted. I will film touching the base tomorrow.

YouTube - Stingo with shorted secondary

At the top it says 50usec/div. Those are the grey squares on the screen. Delta t is the measurement between the two white dotted lines, which I can move to measure things. I will measure the spikes that way tomorrow.

[sucahyo]

You are welcome. What is an h wave?

h wave is a Bedini suggested wave form for charging a battery. A spike and some current after that.

Here is the second video I made today, of the secondary shorted. I will film touching the base tomorrow.

YouTube - Stingo with shorted secondary

Thanks. It do look noise free. I guess the secondary coil have some influence on the primary. I wonder if secondary noise is actually gain?

At the top it says 50usec/div. Those are the grey squares on the screen. Delta t is the measurement between the two white dotted lines, which I can move to measure things. I will measure the spikes that way tomorrow.

Thanks .