inputs.text: basic cheap works - forget instructions press button hold scales steps hold antenna close target get decent reading relative signal strength bar graphi tested 2 fm transmitters one old 70s era kit no pll occasionally needs tuning one amazon bought gem programmable phaselockedloop frequency stabilitythe counter able detect accurately devices although touch antenna base kits antenna get reading probably less 100 milliwatt outputthe amazon bought transmitter tested couple feet although nominally 100 milliwatt setting alsoit also picked wireless router 24 ghz though hold antenna directly base antenna routerfor need another gizmo job