Abstract: A mechanism for driving a television tuner channel indicator located behind a panel and mounted concentrically with a selector shaft and a concentric fine tuning shaft. The driving mechanism includes a two-piece gear housing mounted on the selector shaft for rotation therewith, a driving gear affixed to the fine tuning shaft, a driven gear, and three planetary gears mounted within the housing and engaging the driving and driven gears. The selector shaft passes through the gear housing and engages the coarse tuning mechanism of the tuner. The driven gear engages the fine tuning mechanism of the tuner, and the indicator is attached to the gear housing. The driving mechanism may be provided with apparatus for actuating an AFC defeat switch when the television tuner is being fine tuned or tuned between channels.

Abstract: A television tuner features a switching voltage generator that resets the voltage across the varicap tuning diodes to about zero voltage when a new tuning range is switched on. This allows the full steepness of the capacitance-voltage characteristics of the diodes to be used in each range. This in turn allows more ranges to be tuned and reduces the effects of stray capacitances.

Abstract: Equalizing system arranged for pulse transmission, adaptive equalization being achieved without the use of an additional periodic adjusting pulse pattern. For this purpose in a control voltage generator the sub-bands and the associated additional sub-bands of an equalized pulse signal processed by the phase and amplitude control circuits are used after pulse regeneration directly as a local reference signal and an adjusting signal respectively. The sub-bands and additional sub-bands are applied to the cascade connection of a comparator and a mean-value device for generating the control voltage which controls the phase and amplitude control circuits in a feedback mode.

Abstract: Disclosed is a digital modem using continuously variable sloped delta modulation and adapted for digitizing voice signals in a telephone system. In the analog to digital direction (A/D), an analog input signal is converted into a digital output, the output logic condition being indicative of the direction of change in amplitude from the last signal input. The signal pulse indicating positive change or absence of pulse indicating negative change is passed to a shift register for transmission of the first pulse signal and storage of a plurality of bits. A feedback network receives the pulse bits from the shift register, and the bits are converted to a summed signal for resolution into a reconstructed or simulated signal against which the incoming signal is checked. For the receiving or D/A direction, a somewhat similar circuit in reverse is used to reconstruct an analog signal from the received data bits.

Abstract: Pulse radar apparatus comprising at least an error voltage generator, a dither-tuned magnetron, a frequency control circuit, a conditional circuit and an angular position indicator connected to the magnetron tuning shaft for turning the local oscillator frequency f.sub.l to a frequency f.sub.lo, showing a fixed difference f.sub.o with the magnetron frequency, where f.sub.o = f.sub.z - f.sub.lo. When, by means of the indicator, the conditional circuit determines that the magnetron is being tuned in a defined frequency range comprising the frequency f.sub.l, the frequency control circuit is alternatively supplied with an error voltage and a voltage proportional to ##EQU1## TO DELIVER A FINE AND A COARSE TUNING VOLTAGE, RESPECTIVELY.

Abstract: A receiver is disclosed for signal-seeking operation on a plurality of channels. The receiver uses power cycling of the RF amplifier stage, mixers, local oscillators and intermediate frequency amplifiers which is in synchrony with the electronic stepping switch used to sequence among the channels. The power which is cycled to these portions of the receiver passes in series through light emitting diode channel indicators.

Abstract: An adaptive feedforward transversal equalizer acting jointly with a data decision-directed demodulating carrier recovery system to achieve substantially jitter-free passband equalization of a suppressed-carrier coherent data signal without the use of pilot tones is improved by adding a feedback transversal filter section operating on past demodulated data symbols. The weighted output of the feedback section is subtracted from the demodulated output output of the feedforward section to provide signals from which data decisions are made and common error signals are derived. Tap-gain coefficients for both feedforward and feedback filter sections and phase angle for the demodulating carrier recovery system are adaptively updated in accordance with the common error signal. Severe frequency offset and phase jitter are simultaneously compensated.

Abstract: A microwave mixer is integrated with an yttrium-iron-garnet (YIG) tuning element to provide a YIG tuned heterodyne conveter or mixer. An input signal is provided to the YIG tuning element by an input coupling loop and local oscillator power is provided to an output coupling loop. A mixing diode is connected in series with the output coupling loop close to the YIG tuning element, and the mixing products appear on the output coupling loop. The output coupling loop is connected to a circuit which separates the local oscillator input signal from the intermediate frequency output signal.

Abstract: A premodulation filter is used to slow the transitions of a digital data signal to reduce spectrum occupancy. Carrier signal generator means provides in-phase and quadrature-phase carrier signals. A first modulation means receives the in-phase carrier signal for modulation by the filtered digital data signal. A second modulation means receives the quadrature-phase carrier signal and a control signal for modulation of the quadrature-phase carrier signal by the control signal. A combining means receives the modulated signals from the first and the second modulation means for providing a combined output signal. An amplitude limiter receives the combined output signal for limiting the amplitude variations in the combined signal. A circuit means receives the filtered digital data signal, and provides the control signal which adjusts the amplitude of the quadrature-phase carrier signal to complement the amplitude of the modulated in-phase carrier signal.

Abstract: A pulse transmitter-receiver system for detecting the presence and proximity of objects employs transmission of short base-band or subnanosecond electromagnetic signals and reception thereof by a dispersionless, broad band transmission line antenna system with a receiver circuit cooperating with a biased semiconductor diode located within the transmission line antenna system for instantaneously detecting substantially the total energy of each reflected base-band pulse and for providing corresponding outputs suitable for indication of the presence or of the range of such proximate objects.

Abstract: Telecommunication is effected by generating a beam of mu mesons or muons, varying a property of the beam at a modulating rate to generate a modulated beam of muons, and detecting the information in the modulated beam at a remote location.

Abstract: A modem having a transmitter portion including a first modulator connected to receive audio frequency signals and supplying an output signal through a single sideband filter to a second modulator providing an output signal at a unique channel frequency, a receiver portion including a first demodulator connected to receive transmitted signals and supplying an output signal to a second demodulator through a single sideband filter with the second demodulator providing audio frequency output signals, a carrier switch supplying a small amount of the carrier to the second modulator during operation of the transmitter and a carrier level switch associated with the carrier switch for supplying the carrier at high and low levels, and a crystal controlled channel oscillator connected to the second modulator of the transmitter portion and the first demodulator of the receiver portion with removable, plugin crystals connected thereto for controlling the channel frequency of the modem.

Abstract: A self-contained alarm signal apparatus is disclosed which comprises an electrical signal generator, and encoder connected to receive the output of the generator and to encode a message to be delivered to a transmitter, a source of stored mechanical energy, and connector means for intermittently applying energy from the energy source to the generator for production of an electrical signal. Also provided are first and second input devices for delivering mechanical inputs to the connector means, each of the mechanical inputs operative to cause the connector means to apply energy to the generator. The first input device comprises manually actuable means and the second input device is automatically operable and comprises a timer and means to deliver a mechanical input to the connector means at predetermined time intervals.

Abstract: A method and apparatus is described for generating a data stream incorporating a self-clocking Manchester type code. The data, originally stored in a shift register, is shifted out of the register in bi-level form with a first voltage level representing one binary value and a second voltage level representing a second binary value. The output voltage levels from the shift register are applied simultaneously to two AND gates with an inverter interposed between the shift register and one of the AND gates. Two clock pulse trains are utilized, one having a clock rate twice the clock rate of the other. The clock pulses are respectively applied to the AND gates, the outputs of which are OR'ed and applied to a flip-flop. The output pulses from the OR-gate clocks the flip-flop which toggles to provide a suitably encoded self-clocking data stream at the true and the not true outputs thereof.

Abstract: A method and apparatus is described for receiving a data stream incorporating a self-clocking Manchester code. The data stream is applied to monostable multivibrators which produce pulses at each positive-going and negative-going transition in the voltage level of the data stream. Output pulses from the monostable multivibrators are applied to a third monostable multivibrator which is responsive to only the positive-going pulses applied thereto; the third multivibrator produces an output pulse having a period greater than one-half the bit period, but less than the whole bit period, of the data stream. The positive-going voltage transition of the output of the third multivibrator is used to trigger a clock pulse which is applied to a pair of gates. The gates enable a pair of latches to which the data stream is applied to recover data from the stream and apply the data to a shift register.

Abstract: A channel indicator device is disclosed in which a tuner for achieving station selection between VHF and UHF band television broadcastings is provided in association with a single channel selection shaft of the tuner, a switch for band selection is also provided in connection with the channel selection shaft, and an indicator in the type of a plural-unit indication is provided, the indicator having a numeral corresponding to a selected channel in response to the channel selection and a code corresponding to a selected one of the VHF and UHF bands. The indicator has provided with a plural-unit indication member consisting of a plurality of indication elements to form a numeral "8".

Abstract: An automatic oscillator frequency control is provided for operations such as employed in channel selection in radio and television receiver systems. A code is stored representative of a selected frequency band within which a selected channel is located. The frequency of an oscillator is varied monotonically from a reference frequency at one extremity of a selected frequency range successively to traverse a plurality of such frequency bands. A frequency marker is generated at the margin of each band and the markers are counted. The number of counted markers is compared with the stored code to generate a control state. In response to the control state, a pattern control causes it to dither between limits of the selected band until a signal is encountered at the selected frequency within the selected band. At that point, the oscillator is locked to the frequency of the received signal.

Abstract: In a tuning apparatus for a broadcast receiver having a voltage controlled variable frequency oscillator for generating a local frequency signal corresponding to a selected broadcasting station, and being provided with a phase locked loop including a reference signal oscillator, a variable frequency divider which receives the local frequency signal, usually through a prescaler, for further dividing the local frequency signal with a variable dividing ratio, and a frequency and phase comparator for comparing outputs of the reference signal oscillator and the variable frequency divider, respectively, and producing a corresponding control voltage which is applied through a low pass filter to the voltage controlled oscillator for determining the local frequency signal in dependence on the dividing ratio of the variable frequency divider; a dial member is provided with a scale calibrated to represent broadcast frequencies over a predetermined frequency band and cooperating with an indicator movable along the scale

Abstract: A bandstart detector system for a television receiver tuning system wherein a sample of oscillator signals utilized for conversion of radio frequencies into intermediate frequencies is coupled to a plurality of tuned circuits. Detecting means are coupled to each of the tuned circuits to produce control signals having an amplitude inversely related to the difference between the oscillator signal frequency and the resonant freqency of each of the tuned circuits. The amplitude of the control signal will vary as the oscillator signal frequency is swept in a regular manner through a predetermined band of frequencies corresponding to television channel frequency allocations. The control signals are coupled to a sensing circuit which produces one output signal when the control signal is below a predetermined level and a second output signal when the control signal is above a predetermined level.

Abstract: A television tuning system employing a varactor tuner in which the local oscillator frequency is time sampled by an asynchronously gated counting system to provide tuning information for a channel number computer. The computer has a presettable modular scaler and presettable units and tens counters to derive the corresponding channel number and a fractional portion of the intrachannel spacing. A comparator is coupled to the channel number computer for comparing the derived channel number information with the desired or input channel number information. A keyboard-selected channel number is encoded and stored in a memory which supplies the information to the comparator and to a decoder display unit for visually displaying the selected channel number. The memory also supplies information to a band decoder which provides band preset information to the channel computer and selectively activates the VHF and UHF tuners.