Fangrui Product Details This Is A 1.2ghz Frequency Meter. All Settings Are Automatically Saved And Can Be Called Directly When The Machine Is Turned On. The Frequency Reference Uses A Temperature-compensated Voltage-controlled Crystal Oscillator (2.5ppm -tcxo). The Gate (display Refresh) Time Is 0.01 Seconds/0.1 Seconds/1.0 Seconds, And The Frequency Value Is Displayed In Real Time. Single-ended Input Design, Three Frequency Measurement Channels (low Channel/high Channel/automatic Channel) Are Optional, Dual Intermediate Frequency Design, Intermediate Frequency Value And Plus/minus Mode Can Be Preset Separately. Simple Circuit, Reasonable Structure, Dual Button Control, Simple Operation. Working Voltage:dc9v-15v (with Reverse Polarity Protection) Working Current:maximum 160ma Display Digits:eight-digit Led Display, Up To Eight Digits Display Brightness:eight-level Led Brightness Adjustable, Factory Set To The Highest Brightness Gate Time:0.01 Seconds/0.10 Seconds/1.0 Seconds Measurement Channel:low Channel/high Channel If Sett