The primary distinction is the ability of the PowerAIM to make readings in the presence of strong RF interference. The AIM4300 can tolerate up to 0.1 volt of stray RF at it's input, the PowerAIM120 can tolerate up to 25 volts, while the PowerAIM150 can tolerate stray RF up to 150 volts peak. Click for latest program for the PowerAIM150 Features: Frequency range 50KHz to 150 MHz Temperature compensated crystal oscillator Averaging of scans up to 256x TDR function for cable and connector evaluation Type-N RF connector Multiple sensitivity ranges for precision measurements of components Compatible with Windows computers and tablets running Win XP, Vista, Win 7, 8 or 10 The parameters that are calculated include: SWR referenced to any impedance Resistance and reactance at the cable input Resistance and reactance at the antenna terminals Resistance and reactance of discrete components Return loss Reflection coefficient Cable length Cable impedance Cable loss Distance to fault (open or short) Marker sets to collect data at specific frequencies Two Smith chart displays Band scan for interfering signals Quartz crystal parameters TDR (Time Domain Reflectometer) for cable evaluation The scan data can be saved to disk or printed to compare before and after results. It can also be imported into spreadsheet programs for further analysis.

The PowerAIM150 software features include all the capability of the AIM4300 and it has additional features designed for commercial antenna system testing. The following example uses a PowerAIM120 to show how measurements can be made on a 160 meter vertical even when strong broadcast stations are only a few miles away. The disturbance due to each station extends only about 20KHz around the carrier. The PowerAIM150 is similar but it can handle much stronger interference levels than the PowerAIM120. A report on this evaluation study is available here. Sept 6, 2016