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PWM 1Khz-500Khz Packet Pulsing w/ Gating

  1. Sep 28, 2008 #1
    Hello everyone,
    First time posting here, thanks in advance to anyone who can help.

    I'm building an HHO generator, otherwise known as a water fuel cell, or high efficiency electrolyser. The concept is to separate water using a high voltage signal at resonance instead of current.

    What I need to do is build a DC square wave generator that can pulse a step up transformer coil and induce high voltage discharges. I've tried building several circuits using the LM324 and 555 timer chips, but none can compare with the performance of this unknown circuit, who's waveform is shown here:
    http://hydrogencollective.com/PacketPulser1.mpg

    I think this is a modified version of the so called Dave Lawton D14 circuit, using two 555 oscillators, shown here http://students.umw.edu/~jsera9mu/wfc%20site/index.27.bmp

    Any thoughts on how to modify the D14 to emulate the wave in the video?
     
  2. jcsd
  3. Sep 29, 2008 #2

    berkeman

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    Staff: Mentor

    Seems like a better approach would be to use digital oscillators to make your waveforms, instead of 555 timers. Use a 74HC4060 with a crystal as the digital waveform source, and add some digital circuitry after all of the divider outputs to make whatever waveform you want...

    http://www.lookrs232.com/img/74hc4060.gif
     
  4. Sep 29, 2008 #3
    Thanks berekeman,
    That schematic looks good, could you explain what the q4-q7 are with the 9600, 4800, 2400 and 1200 next to them? Is the 2.4 mHz a maximum? I'm really at a loss about microcontrollers? if thats what this is, I'm guessing programmable via software and interface with usb perhaps?

    An advantage to the whole setup would be the ability to detect resonance frequency, using a phase lock loop design. This occurs when input frequency matches output frequency, so the ability to measure output and set input is eventually going to be necessary.
     
    Last edited: Sep 29, 2008
  5. Sep 29, 2008 #4

    berkeman

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    Staff: Mentor

    Ah, sorry. It's a 14-bit ripple counter with oscillator capability included:

    http://www.national.com/ds/CD/CD4020BC.pdf#page=1

    So you connect a crystal (and a couple other parts) as shown in the datasheet, and then connect logic to the outputs of the ripple counter. Keep in mind that it is a ripple counter, and not a synchronous counter, so you need to be careful how you use the outputs, depending on the frequencies.

    Can you describe in more detail what the waveforms will look like? What is the basic waveform, and how do you want to vary it? If you want to do some PWM control, what range of duty cycle, and what bandwidth do you need on the PWM itself?
     
  6. Sep 30, 2008 #5
    Happily -- the video above is the best summation of the desired waveform. The inventor calls it pulse packeting. A regular DC square wave is generated, with adjustable frequency AND pulse width[_-_-_-_-_]. Then, the signal can be gated, creating pulse trains with variable width, i.e._-_-_-_____-_-_-______-_-_-_____

    The purpose of the adjustable square wave is three fold:
    1, pulsed DC or AC is required for the coil to function, since the output is a result of the collapsing magnetic field in the primary windings.

    2, by varying frequency we can tune the circuit to voltage resonance, where the inductance (coil effect) matches the capacitative reactance (capacitor effect). In this case, the water tank is the capacitor. At resonance, very little amps are consumed and voltage spikes, generating a field strong enough to separate the h20 molecule.

    3, the preferred embodiment of the water fuel cell uses concentric tubes as the electrodes, meaning that the pitch of the wave should match the tubes harmonic resonating frequency, causing ultrasonic vibrations in the tubes which further enhance dissociation.

    Thanks!
     
  7. Oct 20, 2008 #6
    Any takers?
     
  8. Oct 20, 2008 #7
    Sounds like a load of nonsense.
     
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