In order to be aware of the relation cuurent/ time I give you this example:

Resistance of the coil:___1Ohm
Inductance:__________1,5mH
Supply voltge:________36V
Current max.:________36A (as Ufo & Larry mentioned)
_______________________________
63,5% of max current - pulse time: R (Ohm)*C (mH) = 1.5ms -> 22.6A (63.5% of 36A)
99,9% of max current - pulse time: R*C*5 = 7.5ms -> 35.96A
________________________________
10Hz corresponds to_100ms full cycle
10Hz / 50% duty_____50ms pulse

The max. useful pulse time is 7.5ms
The not used surplus time is 50ms-7.5ms=42.5ms -> heat only

Required duty cycle for:
@10Hz: constant 7.5ms pulse:7.5% for 100ms fullcycle(10Hz)
q100Hz: constant 7.5ms pulse: 75% for 10ms (100Hz)

Conversely:
At the arrangement above the optimum frequency for 50% duty cycle and full current use is: 66Hz. Let some margin and go to 70Hz (time is somewhat shorter @50% duty cycle)

Please believe in Ufo employing a coil of 1Ohm. If you get lower it is not easy to handle it! In that case you get an extremely high shark fin for current comprising a short circuit to your battery after very short time.
But don't worrys about your battery! You sacrifice your beloved FETs as fuse! It is like burning dollar notes for heating your home.

Hi Ufopolitiics
I am new to this thread. But after reading the whole thread I am going back to the start because i also want to build your circuits.
i am unable to view your diagram in post 26 .Can you help pse

cheers
Flea

I see it simply as one fet to start of coil, one fet to end of coil. Each on at same time completing the coil charge. Both fets off at same time disconnecting from primary circuit and radiant is lead thru a single wire to a grounded collection device or motor. No radiant goes back to primary circuit to hurt it and the good stuff is now seperate and in our control. Each fet would need its own driver and be close to each fet for exact timing. How simple could it be. When you measure what we put in -vs- what we have in radiant, what is really running the motor. From primary coil, motor gets little when our fets are on, motor gets lots when fets are off and the circuit is safe.
Using secondary coils inside or outside core and of copper or carbon only magnifies this transaction. This is where the magna power is.
Dana

I've been reading through this too with great interest (starting my 2nd read through it now). It seems I have lots to learn first before attempting my own circuit though. The last time I studied electronics was over 10 years ago and I'm a software engineer in my day job, so I've lots to refresh myself on and catch up on.

Apologies if I've missed it but, has anyone fed some of the output back into the original input battery so it's self sustaining? It seems the output voltages are higher than what's put in etc, I was just wondering if anyone had tried it.

You got it.

• It's exactly my opinion but added: usage of opto drivers. They are cheaper than beweeping a bagful blown FETs. And you introduce no extra delays because of different signal propagation.
• Apart that first tests recommended with low side FETs only for proper self eduction. Beginners in electronics need some more runway for start.

Hi John
I have the opto's you talked about on there way. Just cant wait to get the carbon and those opto.s into my circuit.
Dana

Glad you will have them available.
But don't change more than one condition in your setup at same time.

How to proceed:

1. Build unit A (opto driver with FET). Take notes!
2. Test unit A as bottom side switch and and load resistor. Take notes!
3. Test unit A as bottom side switch with coil and get radiant. Take notes!
4. Duplicate unit A as unit B. Take notes!
5. Test unit B as bottom side switch and load resistor. Take notes!
6. Test unit B as bottom side switch and SAME coil and get radiant. Check for identical results A vs. B. Now you have 2 identical functioning units. Take notes!
7. Use unit A & unit B - TESTED circuits - as top and bottom side switches with load resistor. Take notes!
8. Use unit A & unit B - TESTED circuits - as top and bottom side switches with SAME coil. Get radiant again. Take notes!
9. Change other single condition .... Take notes!
10. .....

Less risk MORE fun!

This is an example of how simplicity can be made manageable. You ever ever need to have some notes or alternative building blocks for comparing. In case of malfunction you go back your notes and start at a known functioning point.
It is like stepping up and down a scare. You never will succeed if you try to jump steps of 10 feet hight.
Latin saying: Festina lente! => "make haste slowly"

Thanks UFO
I did read your above mentioned post, but for some reason didn't make the connection. Now I understand.

Regards
Larry

Ian
If you look at the picture I posted on post #1056 of my new pots and note the small circuit under the new pot on the right, that is my cheat for the LM317 regulator. It is a DC to DC converter that takes up to 40V and has adjustable out put of 1 to 36V. The cost from ebay was $1.80 including shipping. I can't post the link right now, but I would highly recommend it.

Hope this helps
Larry

Ian
If you want to use the circuit you mentioned above, place 2 or 3 diodes in series with the input. Each diode drops .7 to 1.5 volts depending on the diode. This will reduce the voltage without limiting the current flow as a resistor would. Select diodes according to current requirements of the LM317 circuit. Even a 50 Ohm resistor would limit the current to 720 milliamps.

Hope this helps
Regards
Larry

Hi and welcome jumping flea
I am not sure why you can't view the image on post 26 it is visible to me. Can you see any of the images on this thread?
Are you going to replicate this circuit.

Regards
Larry

If you are not registered and are here as a guest, you will not see most things. Is that the case here???
Dana

Could well be. If you try again when logged in, you should see it.

Hey Dana,

I am just watching your great strides here...even though I do not comment much...
I think in order to comment you must be a member here...JumpingFlea is a Member...

It is great to know you guys are going into Opto-Isolators, that is a huge advance into this circuits, it will aslo allow use of Higher Voltages at Mosfet's Source-Drains...
We All must thank Mr. John Stone for his great contributions here.

Regards Dana

Ufopolitics

Yes this is the circuit that I am running right now. It works. The problems that I had were my mistakes in trying to use the circuit to run on an NPN when I had run out of the few MOSFETs that I had initially purchased and was waiting for new ones. I had left the diodes from UFOs circuit in and the NPNs didn't like that I guess. anyway it works well now.

Bob

I don't think he could post if not registered... could he?