Kit Of QRM (1-30 Mhz)High Frequency Band QRM Canceller Is there a problem with high frequency local QRM? The answer is usually yes.Whether it's an elevator controller or an arc on a high-voltage line next to a garden.Most problems come from local electronics,computers,TVs,power supplies or otherwise. With this amazing accessory,even the S9,the native QRM can be eliminated.No need to know where the noise is coming from,it could be your own group radio or a welding machine about 100 meters away from you. The QRM canceller plugs into the antenna line without modifying the radio.It has a PTT connection on the back so it can be online while it's transferring.A second auxiliary antenna must be connected,ideally a small antenna close to the noise source,such as a small loop close to an elevator control,or a few meters of wire in a shed or near the main antenna. Keep the antenna short enough or it will pick up the shortwave signal and noise you want.Unwanted signals are picked up by two antennas with different phases,both of which can be added and phased out,leaving your receiver with a clear frequency that is not comparable to a noise canceller. Frequency range: 1.8 MHz-30 MHz Dimensions: 100x100x45mm Connections: Main Antenna,Auxiliary Antenna and 3xBNC for TRX. RCA jacks for PTT The power supply is 5.5x2.1mm Required power supply: 13.8V/150mA. connect: Send the antenna to the main Transceiver sent to TRX Colour:As shown Material:PCB Package Contents: 1 x High frequency QRM canceller Only 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.