Abstract: An airway obstruction luminaire has a luminaire base; a substantially cylindrical Fresnel lens having a lens axis; a halogen lamp having a lamp base, and a substantially linear filament; and a lamp bracket which positions the lamp such that a filament axis of the filament is coincident with the lens axis. The filament is energized by a power supply connected to a first filament end and second filament end, which are separated by an effective length l.sub.E of less than 1 inch. The filament is preferably formed as a helical coil. The lamp is designed to operate at a lamp rated voltage V.sub.L between about 12 and 30 volts. The power supply voltage V.sub.P is reduced if V.sub.P is greater than V.sub.L. The second filament end is supported by a second end support structure configured to reduce shadowing. The lens is preferably an acrylic plastic lens fabricated by injection molding.

Abstract: A mobile system for directing fish away from danger points at an underwater structure includes multiple submersible flash heads operatively connected to a power and control center installed inside a trailer. The flash sequence, rate and intensity are adjustable by the system operator in real time using a system control unit which can be remotely controlled. The flash heads, connected in a tri-pack configuration, are strobed in a manner intended to alter the behavior of the fish. The system may include means to generate an air curtain near the flash heads to improve light dispersion and water jet means to clean the lenses on the flash heads.

Abstract: A system for directing fish away from danger points at an underwater structure includes multiple submersible flash heads operatively connected to a flash head control unit. The flash sequence, rate and intensity are adjustable by the system operator in real time using a system control unit which can be remotely located. The flash heads are strobed in a manner intended to alter the behavior of the fish. The system may include means to generate an air curtain near the flash heads to improve light dispersion and water jet means to clean the lenses on the flash heads.

Abstract: A DC to DC voltage converter using a transformer in which an amplifier driven by a portion of the primary winding opens and closes the primary current path so as to provide self-oscillation and an auxiliary switching circuit cuts the amplifier off at the appropriate point in the cycle faster than achieved by amplifier saturation so as to improve efficiency.

Abstract: A plurality of flash units mounted as warning, navigational or signal beacons are driven from a remote energy storage power converter with reduced number and or size of discharge current cables by common use of cables combined with sequential flashing such that the discharge current for only one flash lamp is carried by a cable at a given instant. By very close spacing, the sequential flashes may be made to appear simultaneous to the human eye.