Abstract: A facility for monitoring the operation of a signal lamp in the outdoor installation of an interlocking. Such signal lamps are powered through lamp transformers located in the immediate vicinity of the lamps. Monitoring for filament breaks is done on the primary side in the interlocking station. The monitoring poses problems in the case of great control distances because leading reactive currents occur on long leads. The invention uses a modulator in the secondary circuit of the lamp transformer which impresses on the lamp current a unique modulation pattern that is recognized in the interlocking station. In addition, the modulator may be turned on via a photocell responsive to the light of the signal lamp, and may perform additional control functions, such as turning on auxiliary light sources.

Abstract: A combined cycle (Brayton and Rankine) system for generating electrical power is disclosed. A gas turbine directly connected to an electrical generator is powered by compressed heated air, the air heated, after passing through the compressor section of the turbine, by passage through a high temperature gas-to-air heat exchanger through which hot combustion flue gases (by burning a biomass or other fuel) are also passed. The flue gases, after passage through the heat exchanger, are used to generate steam for powering a steam turbine or for other purposes.