Abstract: A wedge member usable as a door stop on a carpeted floor. Special triangular cross-sectioned grooves are formed in the lower face of the wedge member to bend and trap carpet pile yarns, whereby the wedge member is prevented from sliding out from beneath the door lower edge.

Abstract: For supplying a bias (modulation) signal, either AC or DC, to a microwave circuit, a network consisting of a low pass filter is provided which presents a high isolating impedance to an extremely wide bandwidth of microwave frequencies, while allowing low frequency bias or modulating signals to be supplied to the microwave circuit without significant attenuation. The network consists of two helical inductors, one within the other, plus a bypass capacitor. The inner small inductor presents a high, non-resonant impedance to high microwave frequencies and the outer, larger inductor presents a high impedance to lower microwave frequencies. The bypass capacitor cooperates with the outer inductor to complete the filter circuit for the lower microwave frequencies. The smaller inductor's proximity to and within the larger inductor provides a distributed shunt capacitance to ground so as to terminate the filter for the higher microwave frequencies at the smaller inductor.