Abstract: A unique bit data operated squelch for use with a demodulator detector for phase shift keyed digital signals. The squelch detects transitions by testing a register of baseband demodulated sample synchronized to the data bit edges. The inventive data operated squelch provides bit detection with programmable parameters and is particularly suitable for implementation utilizing a microprocessor.

Abstract: An improved active balanced mixer for developing an IF signal by combining an RF signal and a local oscillator signal while providing high conversion gain. The mixer utilizes a series resonant circuit resonant at the IF frequency to reduce degenerative feedback effects at the IF frequency, thereby increasing conversion gain. Circuit is particularly adapted for a receiver in which the received RF signal is relatively close to the receivers IF frequency.

Abstract: An improved stackable integrated chip carrierassembly is disclosed which is especially suited for use in printed circuit board with dense configuration of components in limited areas of surface. The chip carrier assembly is mounted on an associated circuit board and allows the vertical stacking of active components in chip form, integral therein. The interconnections of the associated integrated circuit chips are accomplished without soldering which lends itself for easy disassembly when it becomes necessary to remove or replace an internal chip. The chip carrier assembly has an adaptable design allowing single or vertically stacked utilization of the module-like package. To achieve the necessary electrical isolation property, a ceramic cap is placed at the upper most position relative to the integrated module assembled package.