| Patent Number |
Title Of Patent |
Date Issued |
| RE29154 |
Transceiver channel selector |
March 15, 1977 |
| The invention pertains to means for selecting transmit and receive frequencies in a multi-channel transceiver. The superheterodyne-type receiver includes a mixer and a crystal controlled oscillator to provide a variable frequency signal to the mixer, while the transmitter employs a s |
| 4713661 |
Transportation vehicle location monitor generating unique audible messages |
December 15, 1987 |
| A transportation vehicle alert monitor incorporating a speech synthesizer for voice announcement of vehicle location by stop number. The monitor includes a radio receiver responsive to coded RF signals containing either current vehicle location data or data for programming the monitor. C |
| 4660193 |
Digital modulation method for standard broadcast FM subcarrier |
April 21, 1987 |
| A digital transmission system using standard FM broadcast stations employs an SCA subcarrier which is amplitude modulated with a second subcarrier modulated to have different phase orientations representative of digital data. Bits are separated from a digital data stream in groups and ar |
| 4627100 |
Wide band radio receiver |
December 2, 1986 |
| A circuit arrangement for a wide band superheterodyne radio receiver for receiving wide band FM, narrow band FM, and AM modulated radio signals between 25 and 550 MHz. The first LO is a phase locked loop controlled VCO, with central processing unit control of the phase locked loop ci |
| 4590519 |
Television signal scrambling/descrambling system |
May 20, 1986 |
| An in-band television signal sync suppression scrambling system has two sync suppression modes which are aperiodically alternated. Horizontal and vertical synchronizing pulses are equally suppressed in one mode, and are suppressed to different levels in a dual modulus mode. In single mod |
| 4459672 |
Decoder |
July 10, 1984 |
| A load management system which includes a central message generator and a plurality of addressable remote load controllers which selectively connect and disconnect high power deferrable loads to and from a power source in response to transmitted messages. The load controllers include mea |
| 4454509 |
Apparatus for addressably controlling remote units |
June 12, 1984 |
| A load management system which includes a central message generator and a plurality of addressable remote load controllers which selectively connect and disconnect high power deferrable loads to and from a power source in response to transmitted messages. The load controllers include mea |
| 4352992 |
Apparatus for addressably controlling remote units |
October 5, 1982 |
| A load management system which includes a central message generator and a plurality of addressable remote load controllers which selectively connect and disconnect high power deferrable loads to and from a power source in response to transmitted messages. The load controllers include mea |
| 4219821 |
Automatic direction finding system |
August 26, 1980 |
| An automatic direction finding (ADF) system including a direction finding antenna array which connects to a radio receiver to process an audio output signal selectively illuminating a segment of a segmented circular visual directional display indicating the direction from which the r |
| 4057760 |
Frequency synthesized scanner having conductive programming elements for channel selection |
November 8, 1977 |
| A multi-band radio receiver is disclosed for automatically and sequentially tuning to a plurality of discreet, separate preselected frequencies. The receiver incorporates a phase locked loop frequency synthesizer which includes two separate voltage tuned oscillators alternately operative |
| 3996522 |
Crystal controlled stepping radio receiver having novel oscillator circuit |
December 7, 1976 |
| A signal-seeking radio receiver is disclosed which has two different types of local oscillator circuits. One type of local oscillator includes two transistors, the emitter of the first connecting to the base of the second and having a capacitor connecting between the emitter of the secon |
| 3996521 |
Signal-seeking radio receiver with band tuning and selecting means |
December 7, 1976 |
| A signal-seeking radio receiver is disclosed which can be programmed to receive 20 different channels in any combination of three bands with a minimum of switching circuitry. Additionally disclosed is tuning circuitry for tuning the receiver in response to the programming to either the u |
| 3974452 |
Battery powered scanning receiver with synchronous power cycling through electrically operable v |
August 10, 1976 |
| 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 |
| 3974450 |
Dual frequency FM receiver |
August 10, 1976 |
| A receiver is disclosed which will receive signals on either one of two closely spaced frequencies. The receiver is of the superheterodyne type and has a local oscillator frequency midway between the two frequencies which the receiver is tuned to. The receiver also includes a tone squelc |
