Features: Enhance your radio reception with the 300MHz Donut AM MW/SW Mini Loop Antenna Replacement. High Impedance Amplifier is designed to convert high impedance to a standard 50-ohm output, ensuring impedance matching and isolation. Suitable for various antennas like donut whip antennas and magnetic rod antennas, it significantly improves reception performance. For radio enthusiasts, broadcast professionals, and wireless communication buffs, the High Impedance Amplifier is a must-have for any radio receiver, SDR, or walkie-talkie. The High Impedance Amplifier provides reliable signal amplification for passive antenna reception. Perfect for use with donut antennas, magnetic rod antennas, and more. Experience crystal-clear audio and enhanced signal strength with the High Impedance Amplifier. Boost your radio reception and enjoy wide frequencies with this compact and durable aluminum alloy unit. Specifications: Input: 1MΩ Output: 50Ω Gain: 0dB Bandwidth: 300MHz Charging Voltage: 5V Internal Battery Capacity: 800mAH Charging Current: 600mA Working Time: More than 24 hours Size: Approx. 49x45x19mm/1.8x1.9x0.7in Note: No retail package. Please allow 0-1cm error due to manual measurement. Please make sure you don't mind before bidding. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package Includes: Package 1 1pc High Resistance Amplifier Package 2 1pc High Resistance Amplifier 1pc DonutSW Antenna 1pc DonutMW Antenna