potentially adding to the confusing spectrum of modern electo-healing devices, for well over a year now there are some out there being advertised as capable of being switched (like via a slide-switch or rotary dial or button, etc) from TENS mode to Zapper Mode, at the users discretion.
Technically it is true that one does not feel Voltage (meausured in Volts, named after the long-ago scientist Volta) but instead they feel Current (measured in Amperes, named after long ago scientists Coulomb [koo lomb] and subsequently Ampere), but I can tell you this without doubt, the amount of electrical current one feels is the direct result of how much Voltage (electrical force) there is pushing the electrons into the movement we know as electricity. The higher the voltage, the more likely you are to feel the amperes! The other main variable in this forumula is Resistance....yep, you guessed it, measured in units (Ohms) named after yet another long ago scientist, who also formulated Ohms Law, a formula that can be transposed several ways in noting the amounts of the related values (voltage, resistance and current) in a given electrical path or circuit;
E = I X R, where E is mesured in volts (E stands for electromotive force - emf.... a really fancy alternative yet meaningful way of expressing Voltage, I = Current in Amperes, R = Resistance in Ohms. Other ways of stating the same are I = E/R and R = E/I . Coulomb had actually come up with a way of measuring and expressing how many electrons (roughly) were passing a given point in an electrical path due the force of a given voltage, but since this equated to relatively phenomenal amounts of electrons, Amperes evetually became a more practical way of expressing and measuring electrical current. There is another value known as Power that is measured in a unit we know as Watt that is another factor of the related electrical equations. Power/Watts, is an expression of how much energy is dissipated in the process of electricity (movement of electrons) flowing through a circuit (resistance) due to pressure (voltage), for which at the end of the month you get a bill that generally charges you so many cents for each watt used, typically measured in Kilowatts (thousands) or possibly Megawatts.
With devices such as Zapper, the human body - that part of it onto which the zapper output terminals are applied, provides the lion's share of Resistance through which the voltage is pushing the pulsed current. Frequency is a variable that most often comes into play with Alternating Current, however, even though the Zapper is generally designed to use Direct Current, by pulsing this DC on and off so many times per second, a Square Wave output is produced, which is not totally unlike AC. The frequency is anologous to the pulsing, the higher the frequency, the higher the rate of pulsing. Frequency is also interesting since the human body itself, as well as Mother Earth, exists and operates using various systems that each have their own associated internal bio-frequencies, or rate of operation. Hulda Clark
first settled on an approximate frequency of 30,000 CPS (cycles per second, subsequently renamed Hertz by the infamous scientist Hertz), or in other words, the zapper circuit is internally being turned off/on/off to the rate of 30 thousand times per second. Since then, many other zapper designers have chosen lower frequencies, some because they postulate these lower frequencies provide a wider range of parasite-killing effects (due to harmonics, another topic within electronics).
Yeah, it's easy to get lost in the wealth of devices and technologies out there under the general category of Zapper / TENs and the like. My best advice is to spend some quality time reading the archives here as well as broadening your research into other web resources.