Power Supply

V. PCB A. Foil Pattern Layout

B. Parts Placement Guide

VI. Parts List LOW COST REGULATED POWER SUPPLY Semiconductors D1- Rectifier Diode D2- Rectifier Diode Q1- LM317 (voltage regulator) LED- Light Emitting Diode Capacitors C1-2200 microfarad 16V electrolytic C2-1 microfarad 16V electrolytic C3- 0.1microfarad 50V electrolytic Resistors 200ohms

300 ohms

910 ohms

270ohms

120 ohms

200 ohms

180ohms

120 ohms

2k ohms

22 ohms

560 ohms

5k ohms

1k ohms

Others Transformer- 220V Primary, 12V Secondary 75mA SW1- ON-OFF switch (SPST) SW2- Toggle switch (SPDT) SW3- rotary switch • • • • • •

plug and cord PCB Cable tie Solid wires screws fuse holder

VII. Checking and Troubleshooting a. The resistor was not mounted at the right place so power supply did not work. b. voltages exceeds c. toggle switch was burned.

VIII. A. Front Panel

B. Back Panel

C. Top View