Component Rangkaian DC Power Supply:
P1____________500R Linear Potentiometer
P2_____________10K Log. Potentiometer
R1,R2___________2K2 1/2W Resistors
R3____________330R 1/4W Resistor
R4____________150R 1/4W Resistor
R5______________1R 5W Resistor
C1___________3300µF 35V Electrolytic Capacitor (see Notes)
C2______________1µF 63V Polyester Capacitor
D1,D2________1N5402 200V 3A Diodes
D3_____________5mm. Red LED
Q1____________BC182 50V 100mA NPN Transistor
Q2____________BD139 80V 1.5A NPN Transistor
Q3____________BC212 50V 100mA PNP Transistor
Q4 __________2N3055 60V 15A NPN Transistor
T1_____________220V Primary, 36V Center-tapped Secondary
50VA Mains transformer (see Notes)
PL1____________Male Mains plug
SW1____________SPST Mains switch
* P1 sets the maximum output current you want to be delivered by the power supply at a given output voltage.
* P2 sets the output voltage and must be a logarithmic taper type, in order to obtain a more linear scale voltage indication.
* You can choose the Transformer on the grounds of maximum voltage and current output needed. Best choices are: 36, 40 or 48V center-tapped and 50, 75, 80 or 100VA.
* Capacitor C1 can be 2200 to 6800µF, 35 to 50V.
* Q4 must be mounted on a good heatsink in order to withstand sustained output short-circuit. In some cases the rear panel of the metal box in which you will enclose the circuit can do the job.
* The 2N3055 transistor (Q4) can be replaced with the slightly less powerful TIP3055 type.
