Abstract: The invention is directed to an FSL in which a pair of planar ferrite members have planar surfaces in confronting relationship and at least one signal carrying conductor is supported between the ferrites and is closely coupled thereto. A magnetic biasing field is established having field lines disposed at an angle relative to the conductor such that the FSL has an increased attenuation at low frequencies resulting in a relatively flat limiting characteristic across the bandwidth. The conductor may lie in a plane parallel to the field lines or transverse to the field lines. In one embodiment the conductor zigzags in the plane of the field.

Abstract: A frequency selective limiter is described in which first and second ferrite members have confronting planar surfaces and at least one conductor is located on the surface of each ferrite in intimate contact. Each conductor on the first ferrite is a mirror image and is paired to a corresponding conductor on the second ferrite. The paired conductors have confronting end surface portions which are intimately bonded or welded in electrical contact such that each of the paired conductors is electrically equivalent to a single conductor in closely coupled to the ferrites. No other form of bonding is necessary to secure the ferrite members together. In the invention, an external conformal ground plane is more securely deposited in the regions where the ferrites abut. In a particular embodiment, coplanar ground planes located between the ferrites are securely bonded to the conformal ground plane.

Abstract: The invention is directed to a frequency selective limiter. A ferrite member supports a signal carrying conductor and magnets establish a transverse magnetic field closely coupled with the conductor through the ferrite. The magnets establish a magnetic field strength versus temperature having a desired characteristic slope. A magnetic shunt, magnetically coupled to the magnets, diverts a portion of the magnetic field lines away from the ferrite for reducing the magnitude of the field coupled with the conductor to a lower value while maintaining the desired characteristic slope of the magnetic field strength with temperature. In a particular embodiment of the invention, the magnetic shunt establishes magnetic field lines within the ferrite which lie at a selected angle with respect to the conductor so that the limiting characteristic of the FSL is relatively flat across the bandwidth.

Abstract: A miniature waveguide attenuator which may be used in a dominant-mode (TEb.10) waveguide to maintain a low VSWR over a 20% frequency band comprising a short section of waveguide with an E- or an H-plane tee whose width is selected to set the cutoff frequency of the branch line of the tee at the design frequency F.sub.o. The branch line of the tee is terminated in a lossy material followed by a short circuit for absorbing energy propagating down the waveguide at frequencies higher than the design frequency in accordance with a controlled attenuation characteristic.