1. The QRM canceller can be plugged into the feeder of the antenna without any other modifications to the radio.2. Built-in PTT control to keep the canceller connected during transmission. The phase is adjustable, the gain is adjustable in two gears, and the knob is easy to adjust.3. Additional auxiliary receiving antennas are required, such as 2m antennas or wires only a few meters in the shed. The two antennas receive unwanted signals, resulting in different phases.4. The QRM canceller allows adjustment of the phase angle and amplification to cancel unwanted signals before they reach the front end of the receiver.5. Aluminum alloy shell, strong, firm, wear-resistant, high-strength and durable.Product Name: QRM EliminatorThe front and rear baffles are: epoxy glass fiber board FR4Frequency range: 1.8MHz-30MHzSize: 125X110X51mmConnections: 3xBNC for main antenna, auxiliary antenna. For PTT power interfaceRCA connectorsRequired power supply: 13.8V 150mAColour:blackMaterial:Aluminum alloyPackage Contents:1 x QRM Eliminator1 x Antenna1 x AV cable1 x Power Cord3 x UHF/SL16-SMA headOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.