rf - Is it possible to combine two CFU455IT +/-2kHz (4kHz) ceramic filters to get a +/-1.25kHz bandwith (2.5kHz) filter? - Electrical Engineering Stack Exchange
455 kHz filter measuring setup development
10pcs Lt455ew Lt455e Cf455e Cf455ew 455e 1+4 5pin Dip-5 455khz Ceramic Filter For Communication Signal Relays - Relays - AliExpress