LCP50CM and RCP50CM controls the LCP and RCP narrow-band (609 to 613 MHz) filter in the 50cm system on the VLBA. BROAD means do not use the filter, while NARROW means use it. This band is in the UHF TV bands (channel 37) and at some sites the RFI without the filter is so bad that the system will saturate, even for the 90cm system (since the IF will saturate). The filter should be used if at all possible.