Phone patch

An autopatch, sometimes called a phone patch, is a feature of an amateur radio (or other type of two-way radio) repeater or base station to access an outgoing telephone connection.Users with a transceiver capable of producing touch tones (DTMF signals) can make a telephone call, typically limited by settings in the autopatch module to be only to flat-rate numbers, such as local calls or toll-free numbers. The term phone patch more accurately describes a system that is dialed and connected by a user manually operating a base station, which was more common before computer technology made automation of the process easier.

This feature is primarily used by radio amateurs to provide emergency telephone connectivity to places that have lost their telephone network access. An amateur radio operator with a transceiver installed in their vehicle may provide telephone network access from dozens of miles away, depending on the frequencies of the involved repeater/base station, the power of the transceiver, band conditions, and the gain of the antennas on both ends.

In the United States, autopatch users are required to hang up if they encounter music on hold, as the Federal Communications Commission regulations prohibit music on amateur radio frequencies.

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