Dual LPF30-2000W Low Pass Filter


The MFJ-704 Legal Limit Low Pass Filter is an indispensable tool for radio amateurs seeking to enhance their HF operation from 1.8MHz to 30MHz. Crafted with utmost precision, this full-size low pass filter guarantees virtually no loss within its extensive frequency range, ensuring a truly immersive and harmonics-free transmission experience.


Engineered with utmost precision, our LPF30-2000W offers an extremely low passband loss that ensures ultimate signal purity and integrity. Your transmissions will resonate with clarity and authenticity like never before, captivating both seasoned operators and enigmatic listeners alike.

Crafted using only top-quality components and cutting-edge technology, this LPF guarantees impeccable reliability even under the most demanding circumstances. Designed exclusively to complement legal limit linear amplifiers, it flawlessly integrates into your setup without compromising performance or longevity.

Unlock a world of unprecedented audio fidelity as you bask in the seamless connectivity enabled by this remarkable creation. Delve deep into frequency domains previously unexplored while remaining compliant with regulatory frameworks governing amateur radio operations. The Dual LPF30-2000W Low Pass Filter represents an investment in excellence that elevates your amateur radio experience beyond conventional boundaries.

Data was measured on an assembled filter with HP8753ES network analyzer full 2-port calibrated.

Passband1.5 – 29.7 MHz
Insertion Loss 1.8 MHz – 29.7 MHz<= 0.07 dB
Input Return LossBetter than -29 dB
Maximum SWR on any frequency<= 1.074
Nominal Impedance50 Ω
ConnectorsSO239. or “N” by order
Filter Size180 mm x 105 mm x 65 mm
Weight0.7 kg
MountingAny position (5 mm holes for wall mount)
Working EnvironmentIndoor
50 – 54 MHz>= 50 dB
70 – 70.5 MHz>= 52 dB
FM 88 – 108 MHz>= 49 dB
144 – 148 MHz>= 57 dB
222 MHz>= 68 dB
430 – 440 MHz>= 78 dB
Maximum Power Input at 50% Duty Cycle:
SWR 1:12000 W
SWR 1:1.51500 W
SWR 1:21200 W
SWR 1:31000 W

Additional information

Weight1 kg