Decades gone, folks could go to a doctor for aches and pains and be treated with a Diathermy machine. This machine was basically a shortwave radio transmitter, and operated with a curved antenna that fits the human body. When placed against the skin, the antenna radiated energy that was soaked up deep in the body’s tissues. A sufficient power level of RF energy will cause currents of electricity to flow in these tissues, thus making heat. These machines are likely outlawed by this time and died a quiet death in America. RF energy causes molecules to collide with each other making heat. This happens in tisuues like muscles, as well as blood. FM stations ( found in the radio band near TV channel six ) and over the air TV channels two thru thirteen are all in the VHF band. These signals can also pass thru the human body without harm.
These waves are measured in several feet. When you look at any Television antenna, multiply the width of the antenna by 4, which will be the wavelength of the wave from the Television transmitter. Thus the term [*FR3] wavelength, which is a design rule for most antennas. TV channels fourteen thru 83 are in the UHF area. Channel 83 is basically just below analog cell telephone frequencies. Progammable police scanners scan police channels that are terribly close to cell telephone frequencies. ( Privacy laws force scanners to dam the cell telephone band. ) WHERE DOES MICROWAVE BEGIN ? We are now entering the realm where RF starts to affect the human body at a distance.