Manufacturing method of 30MHz-2500MHz electrically tunable filter with low insertion loss

The invention discloses a manufacturing method of a 30MHz-2500MHz low-insertion-loss electrically tunable filter, and belongs to the technical field of electrically tunable filters. The method comprises the following steps: PCB layout: six layers of PCBs are arranged, each layer of the PCBs is grounded in a large area, the ground is laid in the space outside element bonding pads and wires, the wires are arranged on the first layer, the third layer and the fifth layer of the PCBs, and the wires are arranged on the second layer, the third layer and the fifth layer of the PCBs; the second layer, the fourth layer and the bottom layer are completely grounded, and radio frequency pin outgoing lines of a radio frequency switch U1 and a radio frequency switch U2 arranged on the PCB adopt 50-ohm impedance wiring in the first layer and the third layer; the filters arranged on the PCB are arranged in a bilateral symmetry manner; according to the PCB, a large number of grounding through holes are adopted, the grounding e