Skip to main content

Tools Featured in this Teardown

Introduction

This teardown will show the process of taking a continuity tester apart. A continuity tester is a small electronic device that can be used to test a circuit for its open or closed state. The device operates by connecting the positive and negative leads to a circuit and pressing the small black button. If the red light illuminates, the circuit is closed. If it does not, the circuit is open.

This device was fabricated in a Cal Poly Manufacturing Engineering course. All of the resistors, the switch, the LED, and the IC chip were hand-soldered to the PCB.

This teardown is not a repair guide. To repair your Continuity Tester, use our service manual.

  1. Not many tools needed here! Just grab your favorite Phillips head screwdriver. The best size for these small screws is a PH1.
    • Not many tools needed here! Just grab your favorite Phillips head screwdriver.

    • The best size for these small screws is a PH1.

  2. Connect the positive and negative leads to each other. Press the small black button
    • Connect the positive and negative leads to each other.

    • Press the small black button

    • Does the red light come on?

    • If so, battery is in good condition!

    • If not, time for a new 9V!

  3. Start with either side of the device and unscrew the Phillips head sheet metal screw. Remove the screw and set aside in a safe place.
    • Start with either side of the device and unscrew the Phillips head sheet metal screw.

    • Remove the screw and set aside in a safe place.

    • These tiny screws are easy to lose, so grab a ramekin or small bowl to keep track of 'em!

  4. Flip over the device to the opposite side and repeat the sheet metal screw removal.
    • Flip over the device to the opposite side and repeat the sheet metal screw removal.

  5. Separate the top and bottom halves to expose the internals.
    • Separate the top and bottom halves to expose the internals.

  6. Remove the battery connection on the top of the battery. Set battery aside
    • Remove the battery connection on the top of the battery.

    • Set battery aside

  7. Android Fix Kits

    A new screen or battery is one kit away.

    Shop Now

    Android Fix Kits

    A new screen or battery is one kit away.

    Shop Now
  8. Using the same screwdriver, unscrew one of the top screws that holds in the circuit board. Hold the nut on the back with another finger to keep it from spinning.
    • Using the same screwdriver, unscrew one of the top screws that holds in the circuit board.

    • Hold the nut on the back with another finger to keep it from spinning.

  9. Using the same process as step 7, loosen the other top screw.
    • Using the same process as step 7, loosen the other top screw.

    • Don't forget to hold the nut on the back of the screw!

  10. With the nuts off of the screws, remove the two star washers and set them in your bowl of hardware.
    • With the nuts off of the screws, remove the two star washers and set them in your bowl of hardware.

  11. With the nuts and washers off, remove the circuit board from the top shell. With the nuts and washers off, remove the circuit board from the top shell.
    • With the nuts and washers off, remove the circuit board from the top shell.

  12. This is a resistor. There are 5 of them on this board!
    • This is a resistor. There are 5 of them on this board!

    • Here we see the LED.

    • This is the Texas Instruments IC Chip. It is the brain of the operation.

    • This is the Panasonic switch.

    • This is a little diode.

  13. These little spacers keep the circuit board from being smashed against the top shell. Using the best tool (your fingers) remove the first spacers from the screw. Using the best tool (your fingers) remove the first spacers from the screw.
    • These little spacers keep the circuit board from being smashed against the top shell.

    • Using the best tool (your fingers) remove the first spacers from the screw.

  14. Remove the second spacer from the screw. Remove the second spacer from the screw.
    • Remove the second spacer from the screw.

  15. Take the first screw out of the top shell. Take the first screw out of the top shell.
    • Take the first screw out of the top shell.

  16. Take the last screw out of the top shell. Take the last screw out of the top shell.
    • Take the last screw out of the top shell.

  17. Sit back and observe your hard work. Arrange the parts for a nice pic for your portfolio!
    • Sit back and observe your hard work.

    • Arrange the parts for a nice pic for your portfolio!

Brendon Morey

Member since: 10/25/2019

1 Reputation

1 Guide authored

0 Comments

Add Comment

View Statistics:

Past 24 Hours: 3

Past 7 Days: 24

Past 30 Days: 183

All Time: 183