On the test of interphone frequency band

Hehe, this is a handheld frequency meter. The frequency of transmitting radio can be measured near the equipment transmitting radio. For example, walkie-talkies can be measured within two meters. Use a 9V square battery. It is very convenient to use. Press the button to turn it on, and press the button for a long time to turn it off. Just look at the instructions.

The model is GY560, and the frequency can be measured from 50m to 2.4g, including the frequency of mobile phones.

I bought one on Taobao 120, and many of them are sold. You don't need to modify it yourself. Designing and making this should be very complicated. 100 yuan is very convenient to buy one directly.