(2022 upgrade of NanoVNA-F) Nominal Frequency:     10k - 1.5GHz  Scan Points:                  Up to 301 points  Battery capacity:           5000mAh/3.7V  Memory capacity size: 16MB  Up to about 1000 sets of snp file data can be saved.      With the following improvements:     1. The user buttons are changed to a rotary encoder, which makes the control more convenient and smooth.     2. New added RTC circuit, with real-time clock and perpetual calendar functions.     3. Optimize the S21 insertion loss/filter measurement performance, with a larger dynamic range.       Running firmware version: 1.0.4, new features:     1. Add RTC real-time clock, perpetual calendar function     2. The measurement data file name is in the form of YYMMDD_HHMMSS.     3. The frequency setting can choose the start and end or the center span mode.     4. The boot sound can be turned on or off.       This is a vector network analyzer, which can measure the S-parameters of the circuit, transmission test, reflection test, insertion loss, return loss, fault location (TDR function), antenna standing wave, impedance, filter response and so on.