Also, don't forget infrasound - sound at frequencies too low to be audible. They are known to cause low levels of anxiety in sensitive individuals even though t

Also, don't forget infrasound - sound at frequencies too low to be audible. They are known to cause low levels of anxiety in sensitive individuals even though they can't be heard. > An FM transmitter can be at full power even when broadcasting silence. I don't know what phones are like ... do you? I dunno about 3G, 4G and 5G, but I know that a GSM phone (2G) after a data transfer continued to transmit, and at consecutively smaller levels before stopping. The time interval for each level was set by the telco, not the phone.