Abstract: Audio control circuitry for a four-channel system is disclosed which permits volume adjustment from a single master volume control potentiometer and balance adjustment from a single left-right balance potentiometer and a single front-rear balance control potentiometer.

Abstract: 1. A reflectance modulator exhibiting an omni-azimuttal reflectance pattern comprising a microwave lens for focusing electromagnetic energy, a plurality of reflector means positioned on a focal surface of said lens and including a gaseous plasma, means for sequentially controlling the ionization level of said plasma to modulate the reflectance of said energy.

Abstract: Control circuitry for a multi-channel audio system is disclosed which includes left and right signal processing channels and a DC control section. Each processing channel includes balance and volume sections which are connected with the DC control circuitry and controlled from respective balance and volume potentiometers connected with the DC control section. Each channel further includes a tone control section and more specifically treble and bass sections connected with the DC control circuitry and controlled from a tone potentiometer. The response of the bass section is also controlled as a function of the setting of the volume potentiometer to achieve a loudness function. The volume control circuitry is designed to produce a linear relationship between the DC control voltage and signal attenuation as measured in decibels. Current steering circuitry is employed in both amplitude and tone control.

Abstract: Circuitry for developing a binary number proportional to the frequency of an input signal includes a first and second shift register and an adder. Timing control circuitry establishes a 16 bit computation period and also develops a fixed binary number. Circuit means are provided for interconnecting the adder and the firsrt register for increasing the content of the register by the fixed binary number once each cycle of the input signal and for reducing the content of the register by a fixed proportion each of the computation periods occurring during each cycle of the input signal. The content of the first register is transferred to the second or buffer register each cycle of the input signal and display means are provided for displaying the input frequency of a function as the binary number contained in the second register.

Abstract: An integrated circuit responsive to the output of an AM local oscillator and an AFC signal for developing a DC signal for applying a tuning voltage to the front end of a FM receiver which is a function of the local oscillator frequency and the drift of the FM front end.

Abstract: An electronic frequency indicator for an AM/FM receiver utilizing a plurality of light-emitting diodes. The intensity of the diodes is varied to achieve greater resolution for the number of diodes in the indicator.

Abstract: Various switches of a keyboard are connected with a voltage divider network to establish an analog voltage for respective switch closures. The analog voltage is stored on a capacitor and converted by an analog-to-digital converter for input to a computer.

Abstract: An NRZL bit stream is encoded by shifting the bit stream through a 9 bit storage register while logic gates detect and compare the level of adjacent bits stored in the register. The state of an output bit stream is changed if the bits stored in positions 8 and 9 of the register are alike and the change occurs at one or the other of two different times during bit time depending upon whether the pair of like bits are "1's" or "0's". If in addition to the detection of a pair of like bits in positions 8 and 9, an alternate bit pattern is detected in positions 1 through 7 of the register, changes in the output bit stream are forced at a rate of 11/2 bit time intervals until a pair of like bits are detected in positions 5 and 6 of the register. The first of the 11/2 bit time interval state changes occurs at 2 or 21/2 bit times after the state change resulting from detection of a pair of like bits depending upon the level of the bits stored in position 7 of the register.

Abstract: A rotary switch comprising a housing, a cover, three stationary contacts, a rotor, an O-ring seal, and a combination sealing and driving member. The switch is mounted on the end of a door lock cylinder assembly of a vehicle and is connected with the vehicle anti-theft system so that insertion of a key into the lock cylinder and rotation of the key in one direction arms the alarm system through the switch while rotation in the opposite direction disarms the system. The switch is entirely self-contained and weatherproof.

Abstract: A domestic range including a touch control and display panel and digital control logic for energizing power circuits controlling the various range heater elements in response to a program entered by the user by touching certain areas of the panel. The control logic also controls the displays located behind the panel to provide feedback to the user of the program selected.

Abstract: An anti-theft system for a motor vehicle which includes an ARM ENABLE latch and an ARM latch which establish a circuit arming condition in response to movement of a key operated switch from a neutral to an arming position. An ALARM latch is responsive to a plurality of sensor switches which in turn are responsive to whether a compartment of the vehicle is open or closed. If a compartment is opened after the arming condition has been established the ALARM latch causes the vehicle horn to be periodically energized for a predetermined interval of time. Delay means are provided for preventing a change of state of the various latches for a predetermined interval of time after actuation of the switch controlled input to the latch so as to prevent inadvertent triggering of the latch circuit. Indicator means are provided for detecting a malfunction in the system which would prevent the circuit arming condition from being established.

Abstract: A circuit for generating a center tuned pulse for stopping the operation of a signal seeking FM receiver includes means for developing a bias current which is added to the output currents of the quadrature detector of the receiver. A stopping pulse is generated whenever the difference between the output currents is less than the bias current and a 10.7 mHz. signal is present in the IF amplifier.

Abstract: An audio processor is disclosed which includes circuitry for modifying pure left and right audio signals by blending the left audio signal with the right audio signal as a function of frequency and for rolling off the higher frequencies of the blended signal. The processor further includes circuitry for selecting complementary portions of a blended, rolled-off audio signal and a pure audio signal as a function of the RF carrier strength to improve the overall listenability of the audio.

Abstract: The load monitoring circuit includes a solid state current sensor including a positive temperature coefficient (PTC) resistor and a heater resistor. The heater resistor is connected in series with the load and in parallel with the PTC resistor. A third resistor is connected in series with the PTC to form a voltage divider. Current drawn by the load through the heater resistor raises the temperature of the PTC resistor above its anomaly temperature causing the voltage at the divider junction to abruptly switch from a high to a low state to indicate the status of the load.

Abstract: An automatic gain control system in which a DC voltage proportional to an on-channel signal is used to control the gain of the RF stage but is keyed from the wide band output of the mixer stage to reduce the possibility of mixer overload.

Abstract: A circuit for terminating the scanning operation of a signal seeking receiver includes a double-ended limit detector which responds to the AFC voltage developed in the receiver to produce a stop signal when the frequency deviations of the IF signal are within a narrow band centered about 10.7 Mhz.