Hard to say. It depends on:
a) The unit you use
b) The installed options
c) The battery you use: Standard (included) NiMH battery or new (optional) LiPo battery
d) The settings you use (sampletime, frequencyrange etc.)
Examples:
NF-5030 with DDC option measuring 50Hz (HotKey 2):
Regular runtime: Up to 3h
Runtime with optional LiPo battery: Up to 8,5h
HF-2025E Rev.3 measuring GSM900 (Hotkey 7):
Regular runtime: Up to 3h
Runtime with optional LiPo battery: Up to 10h
HF-60100 V4 (all options included) measuring GSM900 (Hotkey 7):
Regular runtime: Up to 2h
Runtime with optional LiPo battery: Up to 6,5h
Also see this posting about the power consuption of all SPECTRAN units: viewtopic.php?f=31&t=852&start=0&hilit=12v+5v#p1813
Snip
OK
The battery runtime of a SPECTRAN unit may vary depending on the specific model and usage. Typically, it can range from a few hours to an entire working day.