Second Hand MFJ-784B DSP Noise Reduction Filter, MFJs tunable super DSP filter automatically eliminates heterodyne, reduces noise and interference simultaneously on SSB, AM, CW, packet, AMTOR, PACTOR, RTTY, SSTV, WeFAX, FAX, weak signal VHF, EME, satellite -- nearly any mode.
You get MFJs tunable FIR linear phase filters that minimize ringing, prevent data errors and have "brick wall" filter response with up to 57 dB attenuation 75 Hz away.
Only MFJ gives you 5 tunable DSP filters. You can tune each lowpass, highpass, notch, and bandpass filter including optimized SSB and CW filters. You can vary the bandwidth to eliminate interference.
Only MFJ gives you 5 factory pre-set filters and 10 programmable pre-set filters that you can customize. Instantly remove QRM with the turn of a switch!
You get MFJs automatic notch that finds and eliminates multiple heterodyne.
You get MFJs adaptive noise reduction. It silences background noise and QRN so much that SSB sound like local FM.
The automatic notch and adaptive noise reduction can be used with all relevant tunable pre-set filters.
Automatic gain control (AGC) keeps audio level constant during signal fade.
Automatic notch filter
MFJs automatic notch filter searches for and eliminates multiple heterodyne in milliseconds. Its so fast, that even interfering CW and RTTY signals are eliminates.
With up to 50 dB attenuation, youll copy stations otherwise masked by heterodyne.
Voice signals arent degraded because the notch is extremely narrow.
Turn on automatic notch and youll never hear unwanted heterodyne or tuner-uppers.
You can selectively remove unwanted tones using the two manually tunable notch filters -- an MFJ exclusive. Knock out unwanted CW stations while youre on CW.
Adaptive noise Reduction
Noise reduction silences background noise, reduces fatigue and makes signals readable.
Noise reduction works in all filter modes and on all random noise -- white noise, static, impulse, ignition noise, power line noise, hiss.
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.
Tune lower cutoff 200 to 2200 Hz and upper cutoff 1400 to 3400 Hz and crate custom filters for Voice, Data and other modes.
Signals just 75 Hz away literally disappear -- they are reduced 57 dB! Unlike other filters, speech is not distorted by unequal time delay.
When signals are weak, you can improve copy by removing noisy high and low speech frequencies that contain little information.
"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.
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.
Only MFJ gives you both tunable filters and pre-set filters customizable for any mode.
Bypass mode lets you hear the entire unfiltered signal. 2.5 watt amplifier, volume control, input level control, speaker jack, PTT sense line, line level output.