MFJ Enterprises MFJ-784B Tunable DSP Filter You can tune the center frequency from 300 to 3400 Hz, and vary the bandwidth from 30 Hz to 2100 Hz -- from super-tight CW filters to wide razor-sharp Data filters. As you reduce bandwidth, interfering signals disappear -- theyre down 47dB, 60 Hz away. These linear phase filters dont distort signals with unequal time relays -- even the narrowest 30 Hz bandwidth doesnt ring. One position gives you two tunable filters you can use together. For example, tune one to mark, one to space and set the bandwidth tight for an incredibly sharp RTTY filters. 15 pre-set filters -- factory set or you program. You can select from 15 pre-set filters. Use SSB, AM, CW, packet, AMTOR, PACOTR, RTTY, SSTV, WeFAX, FAX or any mode. If you dont like our preset filters, you can program your own -- an MFJ exclusive! Save center frequency/bandwidth, lowpass/highpass cutoffs, auto/manual notch, noise reduction -- all filters setting -- in 10 programmable filters. "Slice-off" overlapping SSB signals, hum, pulses, rasp and other low frequency noises. Tunable bandpass filters Narrow band signals like CW and RTTY jump out of QRM when you switch in MFJs exclusive tunable FIR bandpass filters. The LMS algorithm reduces noise by 20 dB and is adjustable to prevent distortion. Tunable highpass/lowpass filters For voice and data, nothing beats MFJs exclusive tunable highpass/lowpass FIR linear phase "brick wall" filters.