User:Srokebep/ENES-100/project 1/tutorial

Build a Power Supply Tester

Target Audience
This is a project for someone who wants to build a power supply tester.

List of material

 * 4 x 2n3055 transistors
 * 1 x 5kΩ potentiometer
 * 2 x 2kΩ potentiometer
 * 1 x 1.2kΩ resistor
 * 1 x 110Ω resistor
 * 4 x .3mΩ resistor
 * 1 x 2kΩ resistor
 * 1 x bread board 3x2
 * 1 x block of wood 1x6x4
 * 4 x 1/8" machine screw 1 1/2" long
 * 4 x 1/8" machine screw 1/2" long
 * 8 x 1" wood screw
 * 2 x aluminum heat sinks 2x4
 * 2' of 12 gauge wirer
 * 2' of 18 gauge solid wirer
 * solder

List of tools

 * electric hand drill
 * 3/8", 3/32", drill bits
 * 1/8" tap
 * Philip screwdriver
 * clamp heat sink
 * soldering iron
 * rubber mallet

Schematic Diagram
schematic for tester

Start the Build

 * 1) Take a heat sinks and a transistor, mark where to drill the mount holes and post holes for the transistors are to be mounted.
 * 2) Do the same for the other heat sink.
 * 3) Drill the holes for the posts with the 3/8" bit and the holes for mounting transistors with the 3/32" bit.
 * 4) Tap mount holes with 1/8" tap.
 * 5) Take all four power resistors and evenly space them apart at one end of the board.
 * 6) Use the wood screws to attach to the board.
 * 7) Peal the plastic from the tape on the bottom of the bread board and attach it to the wood a couple of inches above the resistors.
 * 8) Take one of the heat sinks and mount the transistors to it. Use two of the 1 1/2" screws at at the end of the heat sink and the 1/2" screws for the middle mount holes. The 1 1/2" screws will be used for mounting the heat sinks later.
 * 9) Repeat step 8 for the other heat sink.
 * 10) Take one of the heat sinks and turn it over. Using the 12 gauge wire, solder the wire to the base and emitter as seen in picture. Be sure to clamp the heat sink to the post before you solder, to help protect the transistor from being damaged.
 * 11) Turn the heat sink back over and line up the towards the end of the board with the longer screws 1" in from the side of the board. Using the rubber mallet, tap the screws to make a mark on the board. This is where you will drill the hole to mount the heat sinks.
 * 12) Now drill the mount holes the you just marked, using the 3/32" bit.
 * 13) Back the 1 1/2" screws out half way.line the screws up with the holes, now screw the into the holes.