- This product features four independent bandpass filters, uniquely designed for enhanced listening across distinct frequency bands: - P1 filter: Operates at 0.5-1.5 MHz, ideal for mid-wave radio. - P2 filter: Covers 4.5-12 MHz, perfect for shortwave and low-frequency bands. - The pre-filter for the malachite radio utilizes an all-metal aluminum housing, effectively balancing the design while minimizing interference in mid-wave and shortwave FM broadcasts. - This versatile 4-in-1 filter is compatible with a range of devices including popular receivers, radios, SDRs, and malachite radios, making it a valuable addition to your audio equipment. - The P3 filter (12-30 MHz) functions well in the 40-meter amateur frequency bands, and is also suitable for 20-meter, 15-meter, and 10-meter amateur frequency bands. The P4 filter is specifically designed for FM radio frequencies, operating between 88-108 MHz. - When paired with an active one-to-four splitter, the four-in-one filter offers excellent pre-filtering capabilities for all compatible SDRs, radios, and receivers. Use scenarios: - Enhance your shortwave listening experience by using the P2 filter in conjunction with your SDR for clear reception. - Utilize the P3 filter during amateur radio sessions on various bands, ensuring optimal signal quality. - Connect the P4 filter to your FM receiver for uninterrupted playback of your favorite broadcasts. This product is an essential tool for hobbyists and professionals seeking to improve their radio listening capabilities through high-quality filtering solutions.