Model 3110P is a high performance receiving antenna only. The balun, feedline, and element housing give the 3110P response curves that are almost linear, making it ideal for swept measurements. It uses a sensitive solid state balun tx. Really designed for work within a chamber, as signal powers more than 0dBm (1mW) can saturate above 150MHz.
NOTE: The P after the model number denotes that a collapsible antenna cage is used instead of the fixed cage. This is for ease of packaging.