Filter

The embodiment of the utility model discloses filter, including adjustable signal simulation module and transformer, submodule piece, break -make on -off control submodule piece and on -off switch are received including the control command who connects gradually to adjustable signal simulation module, and control command receives the submodule piece and is used for receiving control command, and break -make on -off control submodule piece is used for controlling the closed of on -off switch or switching on, the input of on -off switch is used for receiving treats the filtering signal, and the frequency channel route of array different frequency is connected to the output of on -off switch, and the frequency channel route is used for the signal through presetting the frequency channel, the transformer is used for being connected with external power, provides the electric energy to other modules among the filter. Filter that this embodiment provided has that filtering is adjustable, electromagnetic compatibilit