Abstract: An optical transmitter includes a light source and an SBS suppression circuit coupled to the light source. The light source is operable to generate an optical signal having one or more wavelengths. The optical signal has a signal spectrum having an upper band limit and a lower band limit. The SBS suppression circuit is operable to communicate a noise current for receipt by the light source. The noise current is operable to broaden the signal spectrum of the optical signal. The light source operates to convert the noise current into a noise component of the signal spectrum that resides between the upper band limit and the lower band limit.

Abstract: A space heater with a linear source of infrared radiant energy in heat exchange relationship with a heat exchanger formed of copper or aluminum material. The copper is pretreated to soften the copper and partially blacken the surface thereof. The aluminum is anodized and electrolytically colored dark. The space heater is thermally more efficient than a comparable space heater wherein the copper or aluminum has not been pretreated. The linear source of infrared radiant energy and heat exchanger are mounted in a heater core that is thermally insulated by an air jacket from an exterior case.

Abstract: A foam body structure formed of plastic foam with one or more flame retardant reception cavities formed in the main body either simultaneously with an initial foam body formation process such as expandable plastic bead molding or subsequent to the foam body formation such as by melting, drilling or cutting. A solid flame retardant such as one in granular form is preferably supplied in sufficient quantity as to entirely fill the volume defined by the reception cavities. A covering or coating is provided over the flame retardant material to fix the material within the cavities. The volume and distribution of the reception cavities and the amount of the chosen flame retardant received in the cavities is sufficient to provide an essentially common flame retardation quality or characteristic over the entire volume of foam body (or at least the volume that could be exposed to a flame in its intended use).