Abstract: A frequency multiplier (120) having a tunable resonant circuit (122), is anticipated for use with a frequency synthesizer (100) having a Voltage Controlled Oscillator (110). The VCO control line (116) voltage establishes the VCO (110) fundamental frequency (.function.o) as well as the resonant circuit (122) center frequency, such that the resonant circuit (122) frequency response will track a desired harmonic component within the multiplier output (130) even as the VCO control line (116) voltage and the fundamental frequency (.function.o) change in response to control line variation.

Abstract: A frequency multiplier (120) having a tunable resonant circuit (122), is anticipated for use with a frequency synthesizer (100) having a Voltage Controlled Oscillator (110). The VCO control line (116) voltage establishes the VCO (110) fundamental frequency (.function..sub.o) as well as the resonant circuit (122) center frequency, such that the resonant circuit (122) frequency response will track a desired harmonic component within the multiplier output (130) even as the VCO control line (116) voltage and the fundamental frequency (.function..sub.o) change in response to control line variation.

Abstract: A tuning circuit for a reference oscillator (200) including voltage variable capacitors (222, 224) in a back to back configuration and providing a control terminal for voltage controlled tuning of the reference oscillator (200). Also included in the tuning circuit is a modulation bias circuit for modulating the reference oscillator (200).

Abstract: A radio having two architectural platforms integrated in one integrated circuit (IC). A synthesizer controller (312) selects between an offset local oscillator (LO) synthesizer (318) and a second LO synthesizer (316) to provide a common architecture for either an Frequency Division Duplex (FDD) or Time Division Duplex (TDD) system design while providing isolation between the two frequency sources. An offset LO signal (319) is translated to an isolated LO signal 310 and combined with a main LO signal (322) to provide the FDD platform. A second LO signal (314) is translated into the isolated LO signal 310 and combined with the main LO signal (322) to provide the TDD platform. The second LO synthesizer signal (314) is common to both systems in the receive mode.

Abstract: A control and antenna mount assembly (100) includes an antenna mount portion (130) having a top portion (132) for mating to an antenna (142). Assembly (100) also includes an insert member (122), control knob (110) having selector contact (118) and a retainer ring (120) all connected to antenna mount (130), together forming a rotary switch, concentric to antenna mount (130).

Abstract: Certain operational characteristics of a crystal (104) are measured during a testing and grading process. Once determined, information representing these operational characteristics are stored in memory (120) and utilized by a controller (122) to increment a phase increment register (114) upon determining the crystals ambient temperature via a temperature sensing circuit (124). The value stored in the phase increment register (114) is then sent to a phase accumulator (116) where successive phase increments are summed together. This summed value is in turn sent to a sine lookup table (118) where the instantaneous phase value is converted into sine amplitude. Finally, a digital to analog converter (126) converts the amplitude bit stream into an analog signal for use as a reference oscillator frequency having extremely high frequency resolution.

Abstract: A communication device (508) for use in a Time Division Multiplex (TDM) communication system (500) includes a transmitter, a receiver, and a frequency scanner for quickly scanning the radio frequency communication channels to determine an available channel. The communication device (508) also includes a phase locked loop (100) for providing a reference signal for the communication device (508) and locking to the available channel. This phase locked loop (100) includes a Voltage Control Oscillator (VCO) (104) having a control signal input (103). The phase locked loop (100) also includes a first filter (110) and a second filter (108). The first filter (110) has a wide frequency response. The second filter (108) includes a storage element (222) and has a narrow frequency response. The phase locked loop (100) also includes a switching circuit (106) which determines which one of the two filters (110, 108) gets coupled to the voltage control oscillator (104).

Abstract: A dual function rotary assembly (100) functions as a potentiometer and a momentary switch. The dual function assembly (100) includes a rotary shaft (106) that when rotated to a predetermined position, such as its final rotational position, may be pulled to provide a momentary contact between two switching terminals (116, 126).