Differing architectures

The Series 2 and Series 5 share the same compact lightweight ruggedized casing, along with the same 4.3” color TFT display and touch-screen user interface.  Under the skin, however, they use significantly different architectures resulting in differing feature sets and power consumption. 
Prices for the Series 5 start at around one third more than for the Series 2.

PSA Series 2

The Series 2 is fully analog, up to and including the detector, using a conventional superheterodyne architecture.

This approach yields particularly low power consumption along with operation down to 1MHz.

The main disadvantage is limited bandwidth filtering choices.

1.3GHz and 2.7GHz models are available both offering more than 8 hours of operation from a charge, and at remarkably low prices.

PSA Series 5

The Series 5 is all-digital from the second IF onwards. This enables it to offer a full range of RBW/VBW settings, multiple detector modes and advanced features such as waveform demodulation and automatic measurements.
Power consumption is higher than the Series 2 (although still much lower than competitive products) and minimum operating frequency is 10MHz.
3.6GHz and 6.0GHz models are available both offering more than 3 hours of operation from a charge, at prices significantly lower than those for comparable portable spectrum analyzers.