A digital copier having a single scanner and a plurality of plotters which are physically independent of each other. The plotters may be designated one at a time. When the designated plotter is already operating, another plotter which is idle is designated. When all the plotters are in operation at the time of designation, image data representative of a document read by the scanner are stored and, as soon as a designated plotter becomes idle, the plotter begins to plot the stored image data auto...

Digital filter arrangement in which a sample of an output signal is calculated by forming the sum of the products of a set of samples of an input signal and a set of filter coefficients. To provide a more accurate encoding of the filter coefficients without great consequences for the hardware, the filter coefficients are encoded by combinations of the form: wherein n and m are integers and it holds that for at least one coefficient: 1<.vertline.K1.vertline.<2 and .vertline.K2.vertline.=0 o...

A digital copier for reducing images printed on a plurality of documents and reproducing the reduced images on a single paper sheet in a desired arrangement. An image forming timing of a scanner and a paper transporting timing of a register roller pair are set up constantly with accuracy by determining a period of time needed for a scanner to move from its original position or home position to a predetermined position and, on the basis of the determined period of time, automatically correcting a...

A digital demodulator utilizes voltage to frequency converters, digital counters and a computer to combine demodulation and analog to digital conversion into one step, therefore providing for in-phase and quadrature demodulation of amplitude modulated double sideband suppressed carrier signals. Accleration sinusoidal signals and phase reference pulses are input to a voltage to frequency converter and counter board which interfaces to a computer where the signals are demodulated using a digital d...

A digital modem is connected to a CBX in a network. Data is transmitted to the digital modem in a data field of synchronous serial data frames. The digital modem converts the data into a digital signal corresponding to a time sampled analog signal representing the data. The converted digital signal is communicated to a digital to analog converter for transmission on a telephone line. Analog signals received on the telephone line are digitized, and then converted to data in the digital modem.

The movement of a rotating part of a machine is monitored by deriving a signal representing the motion of the rotating part, at least temporarily storing the derived signal, and analyzing the stored signal, with temporary storage being performed only on portions of the signal derived during spaced time intervals during each revolution of the rotating part.

An input signal sample is converted, i.e., quantized, from a first digital code to a second digital code by combining an array of stored differential quantizer decision levels with the input signal sample to obtain an array of partial sum signal values. The signs of the partial sum signal values are algebraically summed and the result is used to obtain the quantizer interval that the input signal sample falls in.

An energy conserving thermostatic control system having digitally implemented control functions for use with a heating and/or air conditioning system is disclosed. The digital thermostat includes an LCD data display for simultaneously displaying present time and ambient temperature. Slide switches are provided for setting and indicating set point information such as day temperature, night temperature, night-to-day transition time, and day-to-night transition time. The switch contacts of each sli...

A microcomputer controlled digital thermostat has a two-digit display which normally displays room temperature and a plurality of function and temperature keys for storing control information in the microcomputer. The function keys include a TIME SET key, a HEAT SET key, an AC SET key, and an AC OFF key. The temperature keys include keys for each of a plurality of temperature ranges such as 59.degree.-59.degree. F., 60.degree.-69.degree. F., and 80.degree.-89.degree. F. Time and temperature sett...

Apparatus for sensing and displaying temperature at a site includes a sensor which provides a first current related to temperature at the site, and a circuit for generating a predetermined current. The apparatus also includes a capacitance responsive to a second current having a value proportional to the difference between the first current and the predetermined current for generating a voltage; and means responsive to the generated voltage for discharging the capacitance to a predetermined volt...