Matching Transformers were designed to match your antenna's 75 ohm output impedance to the nominal 50 ohm input impedance of most receivers.
These transformers may be used in almost any receiving application requiring a 75 to 50 ohm conversion. They have a type "F" 75 ohm connection and a variety of output connections, including BNC, SO-239 and a short piece of high quality RG-58 cable with PL-259.
Some of the models include as a part of matching scheme a common mode choke.
Common Mode Choke removes unwanted noise and signals from the feedline of your receive antenna. CMC designed to offer a high impedance path to unwanted signals riding on the shield of the coax, preventing them from entering your radio.
Combined Matching Transformer and Common Mode Choke presents great tool enhancing your receive system capabilities.