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Electrical Engineering/how can DC voltage have a frequncy


QUESTION: The following link has a footbath device OPTIMUM FOCUS-Standard- (ES1550i) with the following ratings: 3.00 Amps/60 Watts, 10,000 Hz outputs.  You will have to scroll down to see the device.

I thought DC currents are direct and therefore have no frequency and only AC currents, which are alternating can generate Hz. The above device claims that the output is DC. See specs of the machine to the right hand side of the webpage.  

The reason I ask, is that another website stated that a unit that puts out 60 Hz could be hazardous to ones health so look for high frequency. Other units marketed are rating at 60Hz frequency output. I am not sure about the medical claims regarding the frequency of the current, but right now I am still trying to figure out how a DC circuit output device can have a frequency rating at all.

Please explain. Thank you, MR

ANSWER: Well, in pure theoretical terms, DC is "0" frequency.

But in the case of the power supply you were referencing it produces DC but also a foldback which is part of the DC regulating system and detects when the current has reached its limit.

I do not understand the foot treatment claims of these products and quite frankly it seems to me to be in the category of witchcraft but that is only my opinion due to my ignorance of this branch of unorthodox medicine.  I think these machines have been outlawed in some parts of the world.  In any event, as an engineer they include a degree of questionable safety - again, my personal opinion.

Sorry to be pessimistic on this subject but if you need more detailed information I would be glad to do some research on a particular question you might have.

---------- FOLLOW-UP ----------

QUESTION: Your pessimism is understandable, I am skeptical too. Regardless of whether it works or not, I am interested in the process to cause ionization.  

Is electrolysis and ionization the same to you?  Ionization is the separation of the H+ and -OH molecules.  I found another company's machine in which there instructions answer these questions:

1. How does the ion cleanse work?

Answer: The ion cleanse switch the 110V AC into 0-24V DC. The mini-computer controller produces the Hz waves with the settled frequency.  The HZ waves are input into the water and change the water characters.

2. What changes happens to the water under the role of the ion cleanse?

Answer: The HZ waves turn the positive electricity potential into the negative one, big- molecule water into small-molecule one and ionize the other matter.

see link and scroll down if you wish: pt=LH_DefaultDomain_0&hash=item3f3257532f

I emailed the seller and asked what frequency or range of Hz he is using to cause ionization.

Therefore, what I am interested in know is if electrolysis and ionization the same?  If they are not, then is an DC current output from the power supply need to be converted back into a AC current for ionization to occur. It appears that "ION Cleanse" machines or detox foot bath must have ionization to occur for them to detox the body as the low current passes through the salt solution bath and through the body.

I am seeing people on youtube who are using 12V battery chargers with 2 Amp output and making their own foot baths and the water changes color just like these detox foot baths sold online.

So now my question is not so much whether a DC current has a frequency or not, but whether a frequency in a current is needed to cause ionization of the water.

If you can explore this more, I would appreciate it.

Thank you, MR

Electrolysis is a well known phenomenon:

Ionization is shown in this URL:

The discussions which I read from  the foot bathing manufacturers sounds like a lot of gobbledy gook to me.  But, I have not studied it in any detail.  But the talk of CHI and Meridians doesn't equate to any engineering terms that I can relate to.   You need a psychiatrist or bio engineer for that type of inquiry!

Have fun.  

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