TX RX 11-36-01, 132-150 MHz, Bandpass Cavity Filters pass one narrow band of frequencies and attenuates all others with increasing attenuation above and below the pass frequency. It is equivalent to a parallel-tuned circuit and is most often used for general transmitter spurious clean-up or a sharpening of a single receiver front end selectivity with or without amplification. TX RX bandpass cavities (4", 6", 8” and 10") have adjustable selectivity characteristics (rotatable loops) to allow a trade-off between insertion loss (0.5-3.0 dB) and selectivity. Maximum power handling is typically determined by insertion loss setting.