... , multilevel interference filters, APC,etc.Main features: high signal-to-noise ratio, strong anti jamming capability, distortion, quality ... good, stable performance, receiving sensitivity adjustable.SystemPower Supply:12V 3AFrequency range: 165MHZ - 270MHZFrequency Stability: ±0.001%Modulation ... Clutter power: < 40dBmBattery:9VWorking Current:≤30mA Portable Speaker Amplifier JP-139