Abstract: A method of a facsimile apparatus includes the steps of providing the facsimile apparatus with a memory which prestores identification information for a plurality of different facsimile machines having common specifications of optional frames, receiving a call for a facsimile communications operation using an optional frame and then identification information from a calling facsimile machine, verifying the identification information sent from the calling facsimile machine with the identification information prestored in the memory, canceling performance of the facsimile communications operation using the optional frame when the identification information sent from the calling facsimile machine is different from the identification information prestored in the memory, and executing the facsimile communications operation using the optional frame when the identification information sent from the calling facsimile machine is identical to the identification information prestored in the memory.

Abstract: In an airplane thrust control apparatus, a control unit (EEC) for controlling the throttle valve opening of an internal combustion engine installed in an airplane and the propeller revolution speed is provided in order to control the engine to appropriate conditions suitable to various flight conditions. During normal operation, the EEC sets the throttle valve opening and the propeller revolution speed in accordance to the stroke of a single power lever. However, if it is determined that the airplane is descending, the EEC sets the throttle valve opening to a value less than the normal set opening, and sets the propeller revolution speed to a high revolution speed equal to or higher than a predetermined revolution speed, regardless of the set revolution speed. Therefore, the thrust control apparatus is able to achieve a sufficient descending rate by reducing the engine output while maintaining high supercharger revolution speed high and maintaining required cabin pressurization.

Abstract: A communications terminal apparatus capable of detecting a busy tone by measuring time periods of a periodic tone state and off-tone state is provided. The apparatus includes a data transmitter and receiver, memory for storing first and second reference time ranges, first and second timers for measuring tone and off-tone state time periods of a signal on a telephone line, respectively, and a busy tone detector. The busy detector detects a busy tone by determining whether the measured tone and off-tone state time periods are within the first and second reference time ranges, respectively, and determining whether the signal alternately includes the measured tone and off-tone time periods.

Abstract: According to the supercharging pressure control device of the present invention, the speed of the turbocharger of an internal combustion engine for an aircraft is controlled by adjusting the opening of a waste gate valve. In the control device of the internal combustion engine, an inlet air flow rate of a turbocharger compressor, an inlet air pressure, an inlet air temperature, and an air-fuel ratio of the internal combustion engine are detected by respective corresponding sensors. Under these conditions, a pressure ratio of the compressor where the turbocharger is operated near the maximum allowable speed is calculated. At the same time, the waste gate valve opening is controlled so as to obtain the calculated pressure ratio. By this, the turbocharger is constantly operated near the maximum allowable speed. Therefore it becomes possible to operate the internal combustion engine with the maximum supercharging pressure under the operating conditions.

Abstract: A control system for an aircraft that controls the set speed of the propeller governor and the degree of opening of the throttle valve using a single control lever. The speed setting mechanism of the propeller governor is directly connected to the power lever by a push and pull cable, and the set speed of the propeller governor changes in proportion to the stroke of the power lever. Therefore, the propeller speed changes in proportion to the stroke of the power lever. On the other hand, the throttle valve is connected to the power lever by a nonlinear cam and a push and pull cable. Therefore, the degree of opening of the throttle valve does not change in proportion to the stroke of the power lever (i.e., the change in the degree of opening of the throttle valve has a nonlinear characteristic), and the engine output power changes in the nonlinear manner with respect to the change in the propeller speed.

Abstract: An engine including at least two digital computers wherein controlled systems each including a switching unit, an ignitor, and a spark plug are independently provided for each cylinder, and controlled systems each including a switching unit, a drive circuit, and a fuel injector are independently provided for each cylinder. The controlled systems are normally controlled by one of the digital computers, but when one of the digital computers malfunctions, the controlled systems are controlled by the other digital computer.

Abstract: An engine including a supercharger wherein a waste gate valve is provided in the bypass passage bypassing the exhaust turbine of the supercharger and the supercharged pressure is controlled by the waste gate valve so that when the opening of the throttle valve provided in the intake duct falls under a set level, the air-fuel mixture is made lean and when it becomes greater than the set opening, the air-fuel mixture is made rich. When the air-fuel mixture is changed from a lean to rich mixture, the opening of the waste gate valve is made larger to reduce the supercharged pressure and thereby prevent abrupt fluctuations in the engine output.

Abstract: A facsimile machine includes a data transmission speed shift down function according to which the data transmission speed is shifted down from its initial speed to one of a plurality of new speeds based on a ratio between the total number of data frames initially transmitted to a receiver and the number of data frames requested for retransmission by the receiver. In this manner, an optimal new data transmission speed may be accurately and expeditiously determined. A parameter memory containing information regarding destination areas to which an error correction mode of operation is to be used may be preferably provided in a facsimile machine having both of an error correction mode (ECM) and a normal mode. With this structure, the ECM mode can be automatically set. In such a facsimile machine having both an ECM and a normal transmission modes, a common buffer memory is provided for temporarily storing coded image information either in the ECM or normal transmission mode.

Abstract: A facsimile communication method includes the steps of transmitting image information from a transmitter facsimile machine to a receiver facsimile machine through a transmission line, determining whether the receiver facsimile machine is successful in receiving the transmitted image information, sending a first station related to the transmitter facsimile machine a first voice message from the transmitter facsimile machine when the receiver facsimile machine is successful in receiving the transmitted image information, and sending a second station related to the receiver facsimile machine a second voice message from the receiver facsimile machine when the receiver facsimile machine has failed to receive the transmitted image information.

Abstract: In a method for shifting down a data transmission rate at a transmitter in response to a request from a receiver for retransmission of data frames having data errors in a digital transmission system such as a facsimile system, when transmission errors occur, the receiver transmits a request to the transmitter for retransmission of one or more data frames for which one or more data errors have occurred. At the transmitter, the data transmission rate is shifted down from the first data transmission rate to a second data transmission rate which is used for retransmitting the data frames for which one or more data errors have occurred.

Abstract: A method and apparatus for facsimile transmitting having an error retransmission function. A page of information is divided into a plurality of frames. The frames are transmitted on a block-by-block basis with each block having a predetermined number of frames. The information is received at a receiving station and checked for errors. If errors are present an indication is submitted back to the transmitting station so that the frames having errors can be retransmitted. A plurality of buffers is provided so that the first information can be transmitted from a first buffer while the next image information is being encoded and stored in a second buffer.

Abstract: A low cost analog-to-digital converter having a non-linear conversion characteristic produces an output digital signal non-linearly relative to an input analog transmission signal which is applied thereto for demodulation. A compensation circuit having a non-linear conversion characteristic converts the non-linear digital signal output from the analog-to-digital converter into a linear digital signal which has a larger number of bits than the non-linear digital signal.

Abstract: An equalization system wherein a signal received over a line is equalized and the quantity of equalization is compensated based on a difference, or error, between the equalized received signal and a signal which is estimated from the received signal, including a tuning device which compensates the amount of equalization by training, which precedes reception of communication data. A difference or error range which is usable for the compensation of the quantity of equalization is set up during a training sequence. The error range sequentially increases as the training sequence proceeds. Thus, decision feedback updating during the training sequence only occurs so long as the difference between the equalized received signal and a signal which is estimated from the received signal is within the error range, which is sequentially increased during a training sequence. After completion of the training sequence decision feedback updating is always allowed.

Abstract: A synchronization detecting system for data transmission in which a two-dimensionally modulated signal is received by way of a demodulator. In a training sequence for a two-dimensional modulation modem, a point of transition from an alternation to a pseudorandom symbol sequence is detected by producing a sum of the vectors of two signals which are remote from each other by a period of two samples, or a difference therebetween. Whether the detection of the transition point has been correct is decided utilizing the alternation.