Abstract: An aerialift warning system and method for use on aerialift equipment to warn the aerialift operator to fasten his/her safety lanyard and to warn persons within the zone of danger below the aerialift boom/basket of the impending danger posed by the descending boom/basket. The system includes a warning module and a speaker. The warning module includes a driver circuit for receiving a boom movement input signal and for asserting an up motion or down motion signal, and a processing circuit for receiving the up motion and down motion signal. The processing circuit contains an execution program to assert one or more warning messages contained in an audio warning circuit. The asserted one or more messages from the audio warning circuit are sent to a speaker.

Abstract: A dynamic bias stabilization device providing significant control of the operating point and frequency stability of a low-power crystal oscillator includes an inverting CMOS amplifier as its primary gain element and a filtered resistive current source to supply the inverting amplifier with operating power. A number of MOS transmission gates and integrated capacitors configured in a T-type network are used as the amplifier feedback element. The control voltages for these feedback transmission gates are derived from the current source which also supplies power to the crystal oscillator amplifier.

Abstract: A communication system providing read and write access to analog and digitally controlled calibration and configuration information contained within prepackaged crystal oscillators having a crystal oscillator electrical interface with power (VCC), ground (GND), output enable (OE), and oscillator output (XO) interface pins. An output enable (OE) signal is used to control the activity state of the crystal oscillator output, with a pullup MOSFET connected to the XO pin to detect a logic low level at the XO pin during times when the OE signal is logically inactive. A state machine controls access to a serial shift register having multiple calibration and configuration bits. The calibration and configuration bits are used in performing an oscillator specific calibration and configuration function. The state machine also controls the reads and writes of the calibration and configuration shift register.

Abstract: A system which can provide short-range wireless data communication between a base station and a portable low-power module. Each portable module has an identification field by which it can be addressed separately. The identification field (which is 64 bits long in the presently preferred embodiment) can be parallel polled: By commanding all modules within range to respond, the base station can see the 64-bit identification fields combined in what is almost a "wired-OR" fashion. That is, if any one of the portable modules within range is pulsing (reporting a "1" bit) in a given time window, the base station will see a pulse; the base station will see the absence of a pulse only if all of the modules within range are reporting a "0" bit (not pulsing). This can be used, for example, to implement combinatorial logic functions on all (or some subfields of) the 64-bit identification field.