What is ~push to talk~ featur in mobile phones?
For commercial, family and amateur two-way radios, PTT is a button that is pressed when needing to transmit with the radio on the tuned frequency or channel. While the PTT button remains unpressed (or "unkeyed"), any radio traffic that is received on the selected channel or frequency is heard through the radio's speaker. Unless the radio supports full-duplex operation, received audio is usually muted while the PTT button is pressed. Simultaneous full-duplex transmission and reception on a radio is generally not supported unless either the transmit and receive frequencies have significant separation between the two frequencies, or two different antennas are used with enough distance between them, or a cavity filter is used, due to an effect known as desensing which can ...more