Abstract: A control module usable to drive audible or audible/visible output devices in an alarm system can generate a modulated pulse sequence in accordance with a desired output function. Sequence initiating pulses can be transmitted to output devices with a predetermined, substantially constant period. Additional pulses can be coupled to the output devices, between the initiating pulses, and later in time based on functions to be carried out by the output devices. The output devices in turn demodulate the received pulse train and determine the requested function which is then implemented to provide a desired audible or visual alarm indicating output.

Abstract: Strobe control circuitry combines several approaches to limit in-rush current. One circuit limits initial circuit response to an applied voltage that has been switched from an inactive to an active state. Other circuitry switches from a high input impedance state to a low input impedance state a predetermined period of time after the applied voltage has switched to an active state.

Abstract: A strobe light responds to both an input voltage range of about 8-40 volts and a selectable candela output. A programmed processor stores a plurality of electrical parameters which correspond to respective selectable candela. For repetitive fixed periods, the light is repetitively driven by a variable duty cycle signal that takes into account both applied voltage and selected candela output.

Abstract: Strobe control circuitry combines several approaches to limit in-rush current. One circuit limits initial circuit response to an applied voltage that has been switched from an inactive to an active state. Other circuitry switches from a high input impedance state to a low input impedance state a predetermined period of time after the applied voltage has switched to an active state.

Abstract: Strobe control circuitry combines several approaches to limit in-rush current. One circuit limits initial circuit response to an applied voltage that has been switched from an inactive to an active state. Other circuitry switches from a high input impedance state to a low input impedance state a predetermined period of time after the applied voltage has switched to an active state.

Abstract: A multi-candela output device for indicating alarm conditions has an output section, visible after installation, and a mounting section not visible after installation. A candela output level can be set by positioning a manually adjustable member on the mounting section. An indicator of the setting is visible on the output section.

Abstract: Strobe control circuitry combines several approaches to limit in-rush current. One circuit limits initial circuit response to an applied voltage that has been switched from an inactive to an active state. Other circuitry switches from a high input impedance state to a low input impedance state a predetermined period of time after the applied voltage has switched to an active state.