Circuit Project Electronic

To set the above amplifier up, set R1 to max and R12 to 0. After doing this successfully, power on the amplifier. Set R1 so that the measured output offset is between 30 and 100mV. Once set, adjust R12 slowly to achieve a quiescent current of around 120mA. Keep checking the quiescent current as [...]

The TIP2955/TIP3055 transistors should be satisfactory for a power supply feeding a single amplifier. If two amplifiers are to be fed from a single power supply, these transistors should be changed to higher power devices such as the MJ2955/2N3055. Adequate heat-sinking must be provided for whichever transistors are used.
R9 and R10 can be replaced with [...]

This circuit uses a PNP Power Transistor TIP2955, you can use any other according to your current and voltage requirement. Look at R2 a 10 Ohm resistor, when the current in your load to the power supply is less than 70mA the voltage across R2 is less than 10E * 70mA = 700mV right.
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