About the firmware：ATU-100 Latest 3.2 version has flashed [ATU-100 Version] 3.2 version.Compared with version 3.1, some bugs have been fixed. -SWR greater than 1.1 will automatically activate tuning,and the minimum power has been changed from 5W to 1W. 3.2 version can be tuned below 5W.However, Too low value may result in insufficiently fine tuning(original default is greater than 5W auto tuning) , please know this before placing an order. [Product Features]Automatic Antenna Tuner machine with Shell（No battery）,No need to assemble,can use it directly,Automatically tuned developed by N7DDC. [High-quality Accessories] High-quality SMD capacitors, C-channel capacitors, high-quality 1000V high-voltage SMD capacitors, and the PIC chip imported. UHF connector. Parameter Description and inside structure: -Power supply range: 10-15 VDC -Max current: 450mA -Max working power: 100 watts -Max measured power: 150 watts -Minimum power for tuning start: 1 watt -Recommended maximum power while tuning not above 30watts. (after tuningyou can set 100 watts and work on this power) -Minimum measured power: 0.1 watt -Step for measurement on powers under 10 watts: 0.1 watt -Step for measurement on powers above 10 watts: 1 watt -Power measurement accuracy: 10% -Maximum inductance set: 8.5 uH -Minimal step for setting inductance: 0.1 uH -Maximum installed capacity: 1870 pF -Minimal step for setting capacity: 10 pF ATU-100 size description： [Remarkably Compact] The shell of the machine is designed by an excellent designer, compact and exquisite. Weight:550g SIZE: 140 x 88 x 38 mm (L*W*H) Package List: -1 x Assembled Automatic Antenna Tuner machine with Shell（No battery） -DC5.5 x 2.1 power cord*1 -USB 5V to 9V Booster board *1 ATU-100 machine mode description and Instructions: 1. Automatic Mode 0.00_ When a dot "." appears, it means automatic mode 2.BYP Mode 0.00_ When "-" appears, it means BYP mode 0.00 When the dot and-disappear, it means manual mode 3.Test Mode Press the BYP and AUTO buttons at the same time, then turn on the power to enter the test mode. 4.Fast Test Press the TUNE, BYP and AUTO at the same time, then turn on the power to enter the fast test mode. ATU-100 Antenna Tuner Scene: ATU-100 connects to the device： Good condition. ATU-100 Test： Successful completion of the test: connected to the device. ATU-100 Effect： Connects to the device perfect. ATU-100 SWR： Work normally.