The UM-series custom crystal filters from Network Sciences offers bandpass and band reject filters packaged in surface-mount and leaded hermetic enclosures. The UM-series is available in all filter design approximations with several package options. The filters are available from 40 to 200 MHz with fractional pass band bandwidths from .015 to 0.6% in two to ten-pole configurations. The crystal filters are available with delay equalization and are offered in phase-matched sets. These filters feature reduced pass band loss and ripple with 50Ωsource and load impedances as standard. The filter design approximation and number of crystal poles in the filter will determine the stop-band selectivity and ultimate attenuation. The company’s hermetic enclosures offer full military compliance.