Push-to-Talk

Push-to -Talk ( PTT abbr, Eng. Designed for pressures to speak ) generally refers to radio devices, the button to switch from receive to transmit.

Application

Unlike the traditional telephone, where the simultaneous speech of both participants A., is technically possible (full duplex), in voice communications only a mutual Talk of the participants is usually possible (half duplex). The PTT is in these cases to need to turn on the transmitter to start the voice transmission.

Only after pressing the PTT key the signal at the microphone input (speech) signal is emitted by the transmitter of the wireless device via the antenna. When the transmission process to be terminated, the button must be released. During transmission, the receiver of the radio equipment is mostly deactivated since the reception of the own release is not desired.

Technical Realization

For handhelds, the key is usually right on the device. All mobile stations with handheld microphone the key is naturalized there. For base stations with stand microphone button is usually located in the base of the microphone.

Furthermore, the key can also be designed as a foot switch. So the operator has both hands free.

Alternatives

Alternatively to the PTT button Sende-/Empfangs-Umschaltung can also be done with a so-called voice control VOX control ( Voice Operated Exchange, the double meaning of the Latin " Vox " for " voice" is obviously intended).