TFC-2700L Multi-Functional High Precision Frequency Meter 8 LED Display Instrument 10HZ-2.7GHZ High Resolution Frequency Counter  Features: Novel style, lightweight. Cycle cumulative measurement. Both importations frequency ranges: 10Hz to 2.7GHz Highest input sensitivity: 20mVrms. 8 high brightness LED display windows, 0 to 9 characters display simultaneously in cycle a self-test function. Stability:±3*10-9s Specifications: 1. Measurement methods (1) Frequency measurement A channel Range: 10Hz-10MHz (Direct count) 10MHz-100MHz (proportion count) Direct count:1Hz ,10Hz,100Hz(your choice) proportion count:10Hz ,100Hz,1000Hz(your choice) Strobe time: 0.01s,0.1s,1s (your choice) Accuracy: ±count value± base time error ×measured frequency B channel Range:100MHz-2.7GHz Resolution:100Hz,1KHz,10KHz Strobe time:0.01s,0.1s,1s Strobe time:0.01s,0.1s,1s period measurement Input: A channel Range: 10Hz-10MHz Resolution: 10-7s, 10 -8s, 10 -9s (your choice) Accuracy: ±count value± base time error ×measured frequency (3)accumulate measurement Input: A channel Range: 10Hz-10MHz Accuracy: ±1 count impulse Self-check Monitor: 0-9 characters of 8 digital pipe repeatedly shows 2. Input characteristics (1)A channel Input sensitivity: (10MHz) range: 10Hz-8MHz 20mVrms 8MHz-10MHz 30mVrms (100MHz) range: 10MHz-8MHz 20mVrms 80MHz-100MHz 30mVrms Attenuation: ×1, ×20 fixed Wave filtering: low pass, 100KHz,-3dB Impedance: about 1 MΩ (<35PF) Max. Safety voltage: 250V (DC+AC rms) (2)B channel Input sensitivity: 20mVrms Impedance: about 50 Ω Max. Safety voltage: 3V 3. Time base Time base frequency: 10MHz Short-term stability: ±3×10-9/s Long –term stability: ±2×10-5/s Temperature Coefficient: ±1×10-5, 00C-400C Line voltage: Each change ± 10%, the frequency variation ± 1 x 10-7 correspond 4. Power supply voltage: AC220± 10% 50Hz 5. Start time: 20 minutes (<250C) 6. Temperature: working temperature -50C-500C Storage and transportation temperature:-400C-600C 7.Humidity:Working Humidity: 10-90% RH Storage Humidity: 5-95% RH 8. Dimension: 230*200*75 mm 9.Weight :2Kg