Decoder channel selector and enunciator system in an airborne radiotelephone system

Claim 2

In a radiotelephone system for two-way public communication between mobile radiotelephones and call stations interconnectable with telephone telecommunication networks and having a common selective calling and channel code transmit frequency that all mobile radiotelephones of the system are tuned to, and a plurality of two frequency receiver/transmitter talking channels: a mobile radiotelephone having a receiver circuit and a transmitter circuit and responsive to a predetermined selective calling and channel code format; selective calling code specific mobile radiotelephone identifying and responsive decoder and indication activation system means; channel selection means connected to said decoder and indication activation system means via channel select gate means also connected to pass channel code signals when gate activated by said decoder and indication activation system means; channel counter means connected to an output of said gate means and having a plurality of outputs; of a channel decoder connected to said plurality of outputs of said channel counter and having a plurality of individual channel frequency drive output circuits connected to modulate said receiver circuit and said transmitter circuit; microphone means connected to said transmitter and speaker means connected to said receiver for conducting two-way telephone calls from said mobile radiotelephone with said call stations on a selective call basis; wherein said predetermined selective calling and channel code format utilizes pulses generated from tone transitions between at least two preselected frequencies modulated on said common selective calling and channel code transmit frequency with pulse generating means; pulse counter means connected to said pulse generating means and having a four wire 1, 2, 4 and 8 count BCD output; pulse counter decoder means connected to the four wire 1, 2, 4 and 8 count BCD output of said pulse counter means, having a pulse count ''''1'''' output line connected to reset gate means, and having a plurality of digit output terminals; a code match gate having a plurality of input terminals hard wired in predetermined order to a predetermined number of said plurality of digit output terminals as the specific call number for the radiotelephone; and a digit counter decoder circuit having a plurality of input connections from said code match gate and an output connection as the decoder and indication activation system means connection to said gate.

Claim 3

The radiotelephone of claim 1, wherein end-of-digit detector means is connected to said pulse generating means and output connected through circuit means to said reset gate means; and with said reset gate means output connected to said code match gate and through a digit counter circuit having circuit input connection from said end-of-digit detector means and a plurality of output connections to said digit counter decoder circuit for system reset for repeated station calling sequences to that specific radiotelephone.

Claim 4

The radiotelephone of claim 2, wherein said mobile radiotelephones are airborne radiotelephones and said call stations are ground stations connected by common carrier links to telephone telecommunication networks; and having a remote channel decoder connected to said plurality of outputs of said channel counter, and having a plurality of individual channel indicator outputs connected to remote indicator driver circuits.

Claim 5

The airborne radiotelephone of claim 3, wherein the plurality of individual channel indicator outputs of said remote channel decoder are also connected to local select circuitry; a local channel select oscillator connected to said local select circuitry and having an output connection through NAND gate means output connected in a local channel select control loop to said channel counter; and with said channel select gate means output connected to said NAND gate and through said NAND gate to said channel counter means.

Claim 6

In a radiotelephone system for two-way public communication between mobile radiotelephones and call stations interconnectable with telephone telecommunication networks and having a common selective calling and channel code transmit frequency that all mobile radiotelephones of the system are tuned to, and a plurality of two frequency receiver/transmitteR talking channels: a mobile radiotelephone having a receiver circuit and a transmitter circuit and responsive to a predetermined selective calling and channel code format; selective calling code specific mobile radiotelephone identifying and responsive decoder and indication activation system means; channel selection means connected to said decoder and indication activation system means via channel select gate means also connected to pass channel code signals when gate activated by said decoder and indication activation system means; channel counter means connected to an output of said gate means and having a plurality of outputs; a channel decoder connected to said plurality of outputs of said channel counter and having a plurality of individual channel frequency drive output circuits connected to modulate said receiver circuit and said transmitter circuit; microphone means connected to said transmitter and speaker means connected to said receiver for conducting two-way telephone calls from said mobile radiotelephone with said call stations on a selective call basis; wherein a local pulse generator is provided in a local channel select oscillator control loop utilizing said channel counter; with said channel decoder and said individual channel frequency drive circuits pulse counted to the channel selected; local channel select oscillator turn on means; and local channel select oscillator turn off means for turn off of the local channel select oscillator pulse generated count when the chosen channel crystal select drive circuit is activated; and wherein two channel decoders are provided both connected to said plurality of outputs of said channel counter; with a first channel decoder being said channel decoder having a plurality of individual channel frequency drive output circuits; a second channel decoder having a plurality of individual channel indicator outputs; and with local select circuitry connected to voltage supply means, to said local pulse generator, and through individual manual control means to respective individual channel indicator outputs of said second channel decoder for controlled pulse generation start and stop of said local pulse generator.

Claim 7

In a radiotelephone system for two-way public communication between mobile radiotelephones and call stations interconnectable with telephone telecommunication networks and having a common selective calling and channel code transmit frequency that all mobile radiotelephones of the system are tuned to, and a plurality of two frequency receiver/transmitteR talking channels: a mobile radiotelephone having a receiver circuit and a transmitter circuit and responsive to a predetermined selective calling and channel code format; selective calling code specific mobile radiotelephone identifying and responsive decoder and indication activation system means; channel selection means connected to said decoder and indication activation system means via channel select gate means also connected to pass channel code signals when gate activated by said decoder and indication activation system means; channel counter means connected to an output of said gate means and having a plurality of outputs; a channel decoder connected to said plurality of outputs of said channel counter and having a plurality of individual channel frequency drive output circuits connected to modulate said receiver circuit and said transmitter circuit; microphone means connected to said transmitter and speaker means connected to said receiver for conducting two-way telephone calls from said mobile radiotelephone with said call stations on a selective call basis; wherein a local pulse generator is provided in a local channel select oscillator control loop utilizing said channel counter; with said channel decoder and said individual channel frequency drive circuits pulse counted to the channel selected; local channel select oscillator turn on means; and local channel select oscillator turn off means for turn off of the local channel select oscillator pulse generated count when the chosen channel crystal select drive circuit is activated; and wherein two channel decoders are provided both connected to said plurality of outputs of said channel counter; with a first channel decoder being said channel decoder having a plurality of individual channel frequency drive output circuits; a second channel decoder having a plurality of individual channel indicator outputs; and with local select circuitry connected to voltage supply means, to said local pulse generator, and through individual manual control means to respective individual channel indicator outputs of said second channel decoder for controlled pulse generation start and stop of said local pulse generator.

Claim 8

The radiotelephone of claim 5, wherein said individual manual control means are a plurality of manually activated switches, one for each channel of operation; a plurality of impedance devices connected from said voltage supply in series with each switch to said local pulse generator; and a plurality of bias varying circuits individually connected respectively to said plurality of individual channel indicator outputs as the actuating input to said bias varying circuits to individually vary the bias applied to the junction of respective said impedance devices and said switches and through the selected manually actuated switch to said local pulse generator.

Claim 9

The radiotelephone of claim 6, wherein said plurality of impedance devices are a plurality of lamps; with said lamps normally off and subject to insufficient voltage drop when the switch of a lamp is actuated to remain off for an interval with the local pulse generator pulse counting the control loop to actuation of the output connected to the switch actuated of the said plurality of individual channel indicator outputs; and simultaneous turn on of the activated switch lamp and turn off of the local pulse generator with bias change of the bias varying circuit connected to the activated switch with activation of the output connected to the bias varying circuit connected to the activated switch.

Claim 10

The radiotelephone of claim 6, wherein said local pulse generator is an oscillator circuit generating pulses at a much higher pulse frequency rate than the pulse frequency rate generated with a predetermined selective calling and channel code format transmitted from said call stations.