Question

Question #f783d

Answer 1

See the explanation below

Explanation:

Here is a circuit diagram for a `12 "V" "DC"` power supply.

The materials required are :

• The transformer `" TR1 ""230 V AC" "input"`, #15V-0-15V " 1A" " output"#

• 3 diodes `"D1 , D2 and D5 "` `"reference"` `"1N2007"`

• 1 voltage regulator `"LM317T"`

• 1 Zener Diode `"D6 " "11.0V 1W"`

• 1 capacitor `"C1 " "470 "muF`

• 1 transistor `"NPN " " Q1" " BD139"`

• 2 LEDS, one red , one green

• 1 adjustable resistor `"RV1 " " 10" kOmega`

• 5 resistors `"R1 to R5 " " 1" kOmega, "240"Omega " 1/2W, "`

`"2.2 " kOmega, "1 " kOmega, "100 "Omega " 1/2W"`

• Heat sink for the transistor

• switches, wires, solder, board , box