Although a primary building block for duplexers, multicouplers and preselectors, these cavities filters can be used individually or cascaded together to prevent interference or system clean up. Our TX RX Systems brand cavity filter product line consists of four model types. Bandpass Cavity Filters which pass one narrow band of frequencies and attenuates all others with increasing attenuation above and below the pass frequency. T-Pass Cavity Filters are a variation of the Bandpass cavity used for our expandable multicoupler applications. Its general characteristics are nearly identical to a bandpass cavity but the output loop has a pair of N-connectors so it can easily be coupled to other channels.
The Series-Notch Cavity Filters pass a relatively wide band of frequencies while rejecting a very narrow band of frequencies. It is equivalent to a series-tuned circuit.Vari-Notch Cavity Filters pass a relatively narrow band of frequencies and reject (notches out) a relatively wide frequency band.
All cavity filter types mentioned above may be cascaded to achieve an arithmetic sum of individual filter attenuation. Up to 6 dB of additional attenuation can be achieved when the proper length of cable is used to interconnect the cavities.
The 11-37 Series, Bandpass Cavity Filters pass a single frequency while providing a symetrical response on each side of the desired carrier. Variable insertion losses are available while the higher insertion loss will provide better selectivity.