3-1-2 RF BANDPASS FILTER CIRCUIT (RF UNIT)RF bandpass filters pass only the desired band signals andsuppress any undesired band signals. The RF circuit has 11bandpass filters and 1 low-pass filter.(1) 0.03–1.6 MHzThe signals pass through the low-pass filter (L181–L183,C181–C185), attenuator (R181–R183), and are then appliedto the RF amplifiers (Q501, Q601).(2) 1.6–60 MHzThe signals pass through the high-pass filter (L171–L174,C171–C174) to suppress excessively strong signals below1.6 MHz. The filtered signals are applied to one of 11 band-pass filters as below, and then applied to or bypassed thepre-amplifier circuit.