Electronic and microwave components and solid state devices, namely, low pass, high pass, band pass, and band rejection electrical signal transmission filters for high frequency, very high frequency, ultra high frequency and microwave ranges, including those for waveguide and coaxial purposes; optical and microwave channel filters; multiplexers; preselectors, namely, radio frequency preselectors; radio frequency processing devices, namely, equalizers; power dividers in the nature of signal splitters for electronic apparatus; radio frequency modulators; signal frequency modulators for use with telecommunications equipment; converters for converting frequencies both up and down; frequency multipliers; detectors for radio frequencies; detector log video amplifiers, threshold detectors for detecting radio frequencies; amplifiers; pre-amplifiers; electronic and microwave components for telecommunications equipment, namely, directional couplers; diode switches; telemetry converters; and microwave receivers