Morgan Systems M-444 Notch Filter, 75-80 meters

Complement modern transceivers with a Morgan notch filter to lessen or reduce outofband rf energy from nearby transmitters.  A notch filter is the opposite of a bandpass filter:  Instead of allowing a band to "pass" signals and blocking everything else, a notch filter will remove the specified band and allow everything else to pass.  For example: you are operating 20m and 40m stations in close proximity.  The 20m station is getting interference from the 40m station.  A 20m bandpass filter can be used on the 20m station which blocks all out of band signals (everything other than 20m.)  But in severe cases of interference it may not be enough.  A 40m notch filter can be added to the 20m station, which will deeply block or "notch" out the 40m station entirely.  

Notch filters can be used as a standalone product or in conjunction with our bandpass filters for superior performance in an RF busy environment.  Notch filters are perfect for multi-transmitter environments such as field day, SOTA/POTA activations, or contesting.  They are particularly useful with modern direct sampling software defined radios such as the Icom IC-7300.  

Use bandpass filters anywhere that critical single band performance is required, or where nearby transmitting stations cause interference to needed communications. Excellent for multiple-operator stations and portable or field use.

Notch filters use the same compact 3″ square heavy chassis as our legacy model bandpass filters. Units are rated for 200 Watts transmitter power.  SO-239 connectors standard. Packaged with owner’s manual.  Mounting footprint 4"x3".