Abstract: A control used in a two stage HVAC system has a power supply from a 24 VAC transformer which is full wave rectified (D1, D2, D3, D4) to create DC voltages for a microcontroller (U1) and relays (K1-K3). All of the control information needed for the two stage control system is sent to the control from a room thermostat (12) having first and second stage cooling signal terminals (Y1, Y2) over a single line by connecting a diode between the Y1, Y2 terminals creating separate microprocessor recognizable signals.

Abstract: A gas fired furnace system (10) has a controller (14) controlling the supply of gas through a gas valve (12) and air for combustion by means of an induced air draft fan (28), ignition of the gas by means of ignitor (22), the delivery of heated air from a heat exchanger (20) by means of an air blower (34) in response to signals from a thermostat (42). A selected constant flow of air for combustion is provided by controlling the speed of the motor driving the induced motor fan (28) despite changes which may occur in back pressure. Induced draft fan motor parameters proportional to motor torque and motor speed are read on an ongoing basis and inputted to controller (14) which computes a desired voltage and compares that with referenced data stored in the controller memory and makes corrections to the speed of the induced draft fan motor to maintain the constant air flow.

Abstract: A gas fired furnace system (10) has a controller (14) controlling the supply of gas through a gas valve (12) and air for combustion by means of an induced air draft fan (28), ignition of the gas by means of ignitor (22), the delivery of heated air from a heat exchanger (20) by means of an air blower (34) in response to signals from a thermostat (42). A selected constant flow of air for combustion is provided by controlling the speed of the motor driving the induced motor fan (28) despite changes which may occur in back pressure. Induced draft fan motor parameters proportional to motor torque and motor speed are read on an ongoing basis and inputted to controller (14) which computes a desired voltage and compares that with referenced data stored in the controller memory and makes corrections to the speed of the induced draft fan motor to maintain the constant air flow.

Abstract: A temperature control system is shown in which a thermostat circuit is combined with a power supply to produce a higher anticipator current for a W1 signal while reducing power consumption and heat generation of the circuit. A first relay power signal is provided by an unbalanced bridge rectifier (D1, D2, D3, D4, D7, D8) while current drawn through the anticipator resistor (AR1) by means of an additional bridge rectifier circuit (D7, D8, D9, D10) is merged with the first relay power signal. In a second embodiment, an unbalanced bridge rectifier (D1, D4, D7, D2, D3, D8) has an output connected to a first stage relay power signal line as well as to second and third relay power signal lines.

Abstract: A gas fired furnace system (10) has a controller (14) controlling the supply of gas through a gas valve (12) and air for combustion by means of an induced air draft fan (28), ignition of the gas by means of ignitor (22), the delivery of heated air from a heat exchanger (20) by means of an air blower (34) in response to signals from a thermostat (42). A selected constant flow of air for combustion is provided by controlling the speed of the motor driving the induced motor fan (28) despite changes which may occur in back pressure. Induced draft fan motor parameters proportional to motor torque and motor speed are read on an ongoing basis and inputted to controller (14) which computes a desired voltage and compares that with referenced data stored in the controller memory and makes corrections to the speed of the induced draft fan motor to maintain the constant air flow.

Abstract: A redundant power supply system wherein the standby power supplies are maintained in a powered up state at all times by feeding back a difference signal which is indicative of the voltage difference between the output of the power supply and a further difference voltage. The further difference voltage is indicative of the voltage drop across a diode located between the output from the power supply and the load of the entire power supply system.

Abstract: A constant false alarm rate is achieved in a moving-target-indicator radar y controlling the threshold in doppler channels according to the level of clutter in range gates near the range rate being examined for the presence of a target. Processing is simplified by using analog signals in charge coupled devices for target detection.

Abstract: An improved charge transfer device signal processing system is disclosed. In one aspect of the invention the signal at each node of a bucket brigade delay line is detected to provide a continuous output signal over a major portion of a cycle of a multiphase clock. In a different aspect of the invention the signals detected at the respective nodes of a matched filter are selectively summed to negative or positive summation busses to provide an electronically programmable matched filter. In still a different aspect of the invention a charge transfer device matched filter is provided in which both the magnitude and sign of the respective weighted signals can be selectively controlled. There is also provided an improved configuration for detecting the charge required to recharge the two different electrode portions of a split electrode weighted charge coupled device matched filter.