HHO PWM +RPM

I'm one of those HHO shade-tree mechanics. If it only cleans the engine and exhaust, Mother Nature will like it. I'm currently building an HHO unit as I text. I have a good design for a PWM using a 555 chip and a Mosfet. What I want to do is augment the frequency adjustment with the RPM signal from my 1995 Jeep Wrangler to allow for accelleration. THe RPM signal is supposedly digital from a CPU package driving all the guages. THe controlling inputs to my 555 are linier (resistive) so, I expect to "and" or "exclusive or" the RPM signal with the pin 3 output of the 555. Any approaches to this application would be appreciated.

The only available evidence states that water is only electrolyzed while there is current between plates in the cell. The free energy proponents say that the process only works at some undefined frequency.

If you believe that science has got the methodology of electrolysis done accurately, then interrupting current flow only acts to decrease gas production over time. If you buy the free energy position, then you do the process harm by not operating at the "right" frequency.

Nevertheless, if you can give some idea of the tachometer signal, we can probably tell you how to mix it with the pulse train out of the 555.

I don't suppose you can say if the rate of hydrolysis is affected by, or in what way, by the signal applied to the cell? Have you got a figure for rate of gas production with DC applied, and that with various frequencies?

Can you substantiate the claim that the added gas will "clean the engine and exhaust"? Something like Gunk?

ANDing a signal is very different from an exclusive or operation. Can you be more clear about how you wish to change the 555 output with the tachometer pulse rate (assuming there is a pulse train to grab). We do need more information about that.

The hydrolysis is constant with constant DC and a given amount of electrolytic solution. The PWM is a square wave signal output: driving the hydrolysis only on the positive swing. The PWM was originally for those running too hot and drawing to much current. I'm looking to augment my fuel system with a constant amount of HHO (running at a safe level)for normal combustion with the ability to increase hydrolysis just for acceleration. As the tach signal for a Jeep Wrangler it is generated by an onboard computer and in a perfect world is a square wave and if not a sawtooth. Voltage and frequency are unknown at this time. "ANDing" the signals is out..that would negate my purpose, "exclusive ORing" is out also. That leaves just plain "ORing" which gives me the best of both conditions. So maybe I've answered my own questions. Nevertheless any ideas are welcome. Thanks beenthere for your thoughts. For those HHO doublters I'll pass on any 1st hand results. Thanks for help

You can use an op amp and resistive mixing to do the OR function.

We do thrive on facts and figures. Any hard data are welcome.