Need help with Induction bifilar coil on 3/8 graphite rod, no output

Thread Starter


Joined Oct 15, 2008
Hello there,

I am putting together a circuit which is involved with HHO production for a stationary engine. The circuit has a range of frequencies, selectable by 2 switches and they are veriable also, please see circuit.

Part of the circuit involves a 3/8 graphite rod, having 100turns bifilar wound. please see photo.
OK, so far the circuit works up to the output of the mosfet a BUZ350. I can see the waveforms on my cro.

But, I don't know anything about bifilar coils on this setup, as I have not run into them before.

So far I'm getting very confused about a "dot" or polarity. Connecting the wires ends to the circuit may be simple, but is not understandable to me.

I looked at the book section vol 1-DC in the Inductor section and I can follow just 1 coil, but I'm lost at 2 coils (bifilar) on the circuit.

Looking at my bifilar coil, from the left side, the ends I have tagged the wires yellow and blue, at the right or other end of each wire are also tagged yelllow and blue.

The diagram shows how to connect it but, my mind gets thrown by the way it has been drawn and the text is not very detailed how to connect it. Although the ends are numbered 1, 2, 3, and 4.

I need to know which wire goes where on the diagram.
The answer might be simple, but I'm stuck.:p

So far I have blown 2 BUX350s hooking it up wrong.

Any help here would be appreceiated.:)




Joined Apr 20, 2004
Find the wire that goes directly to the FET drain. The other end goes to the cathode plates. On the other winding. the wire that goes to the battery supply comes off the same end as the wire to the cathodes. It's other end goes to the anodes.

Graphite has no useful properties in this application. Soft iron or ferrite would be more likely.

You should take the time to read through this thread, as it has to do with the device you are trying to build -

We will try to help, but have zero confidence in the efficacy of these various schemes of electrolyzing water.
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