Quartz crystals are pieces of quartz cut in a precise manner in order to create a regular and constant electrical frequency. Due to the crystal precision, quartz is used for keeping clocks accurate. The clock measures the vibration of the quartz and displays that reading in the form of hours and minutes. In order to make sure a quartz crystal is precise and constant, you can build a simple tester with some basic wiring skills.
Find a simple quartz crystal tester schematic to follow. Examples of schematics that you can use can be found in Resources, below.
Arrange the electrical components on standard printed circuit board, or PCB, and solder the components in place with a soldering iron.
Connect the wired circuit board to a 9V battery to create a powered tester. Introduce the testing switch by attaching a standard on/off button to the S1 connection on the board.
Set the crystal between the A and B terminals on the testing board, and turn the tester on with the power switch. Chart your results so you can refer to them later.
While the tester will not register crystal strength weaker than one megahertz, anything higher is within the tester's capacity.
Do not attempt to wire a circuit unless you are sure you know what you are doing.