A regulated power supply is used to ensure that the output remains constant even if the input changes. A regulated DC power supply is also called as a linear power supply, it is an embedded circuit and consists of various blocks. The regulated power supply will accept an ac input and give a constant dc output.
Regulated powersupply have voltage regulators on their output. The regulator ensures the output voltage will always stay at the rated value of the power supply, regardless of the current that the device is consuming. This works as long as the device is not drawing more than the rated output current of the power supply. In fancy electrical terms, a regulated power supply provides a constant output voltage, independent of the output current. A regulated power supply with multiple regulators can offer multiple output voltages for operating different devices.
( Warning ) Do not use Un-Regulated Power Supply for Two-way radio equipment, severe damage may occur.