1、This DIY frequency meter can measure the oscillation frequency of most common crystal oscillators and support automatic range conversion. 2、It can measure the frequency range from 1Hz to 50MHz, and the maximum frequency of the signal can be measured up to 30V. 3、Five-digit precision resolution is configured, and the measurement data display is intuitive and convenient. 4、With programmable add and subtract frequency settings, it can be used to measure equipment such as radio transceivers. 5、The power-saving mode can be selected, and the display can be automatically turned off if the frequency does not change significantly within 15 seconds. 6、Wide range of power supply, you can use universal USB interface power supply, also can use external power supply 5-12V or 9V batteries. 7、With all direct-plug components, the number of components is small, the circuit is simple, easy to make, and the installation and debugging are simple.