Mitigating intra and inter station interference during contests.
Protecting receiver circuitry from damage.
Reducing RFI egress and ingress during everyday operation.
Enabling full duplex operation (transmitting and receiving simultaneously) on capable transceivers.
High power handling capability – up to 4,500 Watts ICAS (100 to 200 W for the other guys).
Exceptional out of band rejection, typically > 55 dB and sometimes as high as 75 dB on adjacent ‘contest’ bands thanks to the 5 pole filtering (3 poles are typical elsewhere).
For example, the 20m Series XL filter reduces transmitted and received signals on the 40m and 15m bands by approximately 55 dB or more with higher rejection figures on bands further removed from the primary band. See the VNA plots in this section for typical units. Series XL filters are hand tuned and there are small variances between units.