Solid State Bedini

[blackchisel97]

Hi,

I noticed that in the post above the circuit does not have diodes across the emiter/base, is it ok not to have diodes there? Are the diodes not required because this is not a motor but a self oscillator?

Also, there is one power winding with the trigger winding and then three windings seperate from the first two? How is this coil or coils actual wound?

Are these seperate coils or is there on large coil with 5 windings?

Thank you for any and all help to understand......

Tj

Hi tjnlsn255 First question - answer is yes
This coil is wound on the same spool, all coils together. I twist wire in my setups but this isn't necessary. They look like separate on the schematic but as you see there is one core.


Vtech

[tjnlsn255]

Thanks for the fast reply.....

I will have to give this a try some time.....

Have fun.....

Tj

[wwdotme]

Darlington transistor

I had a tip 102 darlington npn transistor laying around so I hooked it
up to a coil configuration that worked great with a 2n3055 and
I had LOTS of heat build up in the transistor real fast...
ended up with resistors in the 100k ohms range to get the amp
draw down low enough to ease teh heat problem in the transistor.

Might be the transistor sky is using causing his heat problems..
just a thought I'm in no way a pro on here. not sure I could rank rookie
LOL

ww

[tjnlsn255]

Hi Seph,

What is your experience with iron filings for a coil core verses welding rods or other materials?

Thanks for any and all help and insights....

Tj

[Sephiroth]

Iron filings have always worked well for me. Until recently I had only ever used iron filings or atomized iron for my cores (and the laminated steel in pc fan conversions)

Recently tried using ferrites. Ferrites seem to have a much higher saturation than my iron filing mixes, and I think welding rods probably would as well but I haven't done any comparisons...

For solid state I prefer using air core. In motor circuits you want the coils to have very high inductance so that the coil won't reach saturation during one magnet pass, but in solid state this isn't an issue so you can eliminate the core and the losses that come with using a core.

[blackchisel97]

@Seph

but in solid state this isn't an issue so you can eliminate the core and the losses that come with using a core. I agree 100%. I also think that oscillator running in 20kHz range vs 1-2kHz may result in getting closer to the battery resonant frequency, what do you think Seph?


Vtech

[Sephiroth]

but in solid state this isn't an issue so you can eliminate the core and the losses that come with using a core. I agree 100%. I also think that oscillator running in 20kHz range vs 1-2kHz may result in getting closer to the battery resonant frequency, what do you think Seph?


Vtech

I think it may be extremely difficult to get the oscillator even near the resonant frequency of the battery. It would be very interesting if you could do it

[SkyWatcher]

Hi folks, Thank you very much wwdotme for pointing that out about your test comparing a darlington with a single transistor, it solved all my heat problems, the question is how. I'm using a 2n3055 now and it gets slightly warm, I dont even have to put a heat sink on it it stays so cool, whereas before it had thermal runaway, I was using 2 separate transistors before in darlington config. for the joule thief and Bedinis solid state circuit and heating was the same. So there is a problem with using darlington configurations for some reason. What puzzles me is how, with the low gain of the 2n3055 can it turn on properly yet it does, that is why i was sticking with the darlington because i thought it needed that gain at the base, apparently not. The circuit is running beyond my expectations now and no more 555 timer. Thanks again.
peace love light
Tyson

[SkyWatcher]

Hi folks, I rewired my joule thief circuit to this one by Sephiroth, it is even more efficient causing next to no heat in transistor and more output, maybe with the resistor going from the collector to the base its turning on the transistor more effectively and the bifilar not being connected at the high voltage flyback. This circuit is working very well, I would recommend folks try this one, since I've built Bedini's and the JT, this is even better.
peace love light
Tyson

[eternalightwithin]

What did you coat that coil with? I'd like to use liquid tape, but if there is something better I'll use that instead.
Anyone know of a cheap epoxy/polyurethane that has high voltage resistance. (Dielectric strength I believe)

David P

I have looked hard at your circuit agian, and I noticed

1. You are using multiple resistors..... I have not seen this done before.

2. Multiple diodes, which I have seen.

3. No solder connections but using the screw connectors, inovative.

5. Looks like you are using brass solder right on the diode comming out of the transistor to charging battery?

Looking forward to your load test.

[blackchisel97]

I think it may be extremely difficult to get the oscillator even near the resonant frequency of the battery. It would be very interesting if you could do it

I was thinking about resonance which we observed on the scope - ringing pulse in battery and relation with oscillator frequency being higher. I think battery resonance will be in 2-5MHz range. Just wonder if there is significant benefit running higher freq. other than losses in iron core coil.


Vtech

[eternalightwithin]

I was thinking same thing. I don't know, but I think I will hitch up signal generator to the battery and then attach oscillascope probe and see where battery hits resonance. I'm assuming that even comparable batteries have slightly differing resonance points and probably will change over time. (as they become conditioned)

[Sephiroth]

I was thinking about resonance which we observed on the scope - ringing pulse in battery and relation with oscillator frequency being higher. I think battery resonance will be in 2-5MHz range. Just wonder if there is significant benefit running higher freq. other than losses in iron core coil.


Vtech

Yes, the ringing is in the megahertz range... I think it's near impossible to get an oscillator to work effectively anywhere near this frequency, but if you can get it up to the tens of kilohertz range then it is possible you might stumble on a harmonic frequency which will help support the oscillations.

Though high frequency isn't necessary just to cause the ringing like I showed in the other thread . Your oscillator could be operating at just 1hz and still produce the ringing.

Think of the battery as a tuning fork. If you give a tuning fork a short sharp tap, then it will resonate at its natural frequency. The sharper the tap, the more effective the ringing will be.

What's important is the quality of the spike, not the frequency.

Another factor I have thought about is the internal resistance of the battery. Imagine if you were to tap a tuning fork in a vacuum. There would be no air resistance so the ringing will last longer (though you won't hear it of course ). If the battery's internal resistance was to drop (as it does during the conditioning process), I would guess that the ringing at the battery terminals would also last longer. Perhaps this is the difference between a conditioned battery and an unconditioned battery.

[blackchisel97]

Yes, the ringing is in the megahertz range... I think it's near impossible to get an oscillator to work effectively anywhere near this frequency, but if you can get it up to the tens of kilohertz range then it is possible you might stumble on a harmonic frequency which will help support the oscillations.

Though high frequency isn't necessary just to cause the ringing like I showed in the other thread . Your oscillator could be operating at just 1hz and still produce the ringing. You're right

Think of the battery as a tuning fork. If you give a tuning fork a short sharp tap, then it will resonate at its natural frequency. The sharper the tap, the more effective the ringing will be. Yes, I keep thinking this way. Funny, every time it brings in my mind picture of magnetic holder. For some reason it looks like tuning fork

What's important is the quality of the spike, not the frequency. I couldn't agree more. Especially when I can see it now

Another factor I have thought about is the internal resistance of the battery. Imagine if you were to tap a tuning fork in a vacuum. There would be no air resistance so the ringing will last longer (though you won't hear it of course ). If the battery's internal resistance was to drop (as it does during the conditioning process), I would guess that the ringing at the battery terminals would also last longer. Perhaps this is the difference between a conditioned battery and an unconditioned battery.

I think that's exactly what J.B is talking about. I believe also that there will be many interesting things happening once battery becomes conditioned.



Vtech

[SkyWatcher]

Hi folks, wow thanks for this interpretation Sephiroth, that makes good sense, quote "Yes, the ringing is in the megahertz range... I think it's near impossible to get an oscillator to work effectively anywhere near this frequency, but if you can get it up to the tens of kilohertz range then it is possible you might stumble on a harmonic frequency which will help support the oscillations.
Though high frequency isn't necessary just to cause the ringing like I showed in the other thread . Your oscillator could be operating at just 1hz and still produce the ringing.
Think of the battery as a tuning fork. If you give a tuning fork a short sharp tap, then it will resonate at its natural frequency. The sharper the tap, the more effective the ringing will be.
What's important is the quality of the spike, not the frequency.
Another factor I have thought about is the internal resistance of the battery. Imagine if you were to tap a tuning fork in a vacuum. There would be no air resistance so the ringing will last longer (though you won't hear it of course ). If the battery's internal resistance was to drop (as it does during the conditioning process), I would guess that the ringing at the battery terminals would also last longer. Perhaps this is the difference between a conditioned battery and an unconditioned battery.". That is worth repeating.
Your solid state circuit is working extremely well, even though yes it is Bedini's circuit without the extra resistor going from base to ground. All I have to do to charge smaller batteries is to adjust the collector to base resistor. I'm charging/conditioning lead acids, alkalines, zinc carbons, nimh with this solid state oscillator and it's working nice.
peace love light
Tyson