Bob Boyce TPU thread

[Bob Boyce]

Hi Bob,

Thanks for the updates to the circuit board. I personally am very interested in driving the primaries with one-wire input (since I have done that before with a function generator for a transformer and it works great). I have some questions for you:

1. As for the diagram, do you have any rough recommendations for the circuit component values?

2. I took a look at the driver chips you mentioned. I am going to order some samples myself. They are definitely superior to the ones I am using since they can charge a twice the capacitance mine can in the same time. How would you connect the open ended coil to this? Just tie one lead to the output pin?

God Bless,
Jason O

Which diagram and components?

Yes, those TI drivers have a very nice output stage. Bipolars and FETs for pulling high and low very fast.

Bob

[Jdo300]

Hi Bob,

I was referring to the very last diagram you showed in your last post. Also, I attached a simple one-wire pulse circuit that I thought of. Is this how you would drive your primaries in one-wire mode?

The other way (which I have tested already) is this circuit here:



The only thing is that the transformer modifies the pulses going into the coil (which in my case was a good thing since it increased the voltage). But you have to use the right kind of transformer or it doesn't work at all.

God Bless,
Jason O

[eldarion]

OK, I was doing some experiments on my air-core coil, and I noticed this.  What is it?  Is it part of the energy conversion process trying to start but not starting because of my air-core coil?  Or is it just something normal?  I didn't see it on the scavenged toroid, so I was curious.

Thanks!

Eldarion

[Jdo300]

Hey Eldarion, how is your air core toroid wound? By the way, i can chat with you now if you get on Skype

[Jdo300]

Hi all,

I just finished building and testing the attached circuit. I used Earl's Flip flop idea (adapted for a JK flip flop) to get the pulse width very small, and I used a mic4427 driver as the output stage. The output pulses were about 180 ns wide wit ha rise time of 20 ns. The circuit worked great except for the fact that it was made on a breadboard which, as Earl mentioned, has a lot of capacitance. There was also some crosstalk between some of the traces which influenced the output if you set both input frequencies close to each other.

I used this circuit to test pulsing a single coil from both ends with frequencies. I didn't see anything miraculous but I was able to pick up beat frequency oscillations on other coils (when tested on my TPU). No significant power but one thing is for sure. The one-wire pulse does work. I also used just one of the outputs on the circuit and connected it to one side of the primary of a transformer. I was able to charge up a capacitor on the secondary with the rectified output from the transformer. Keep in mind that I only used the circuit below, no FETS at all .

God Bless,
Jason O