Multi-channel communication device with manual and automatic scanning electronic channel selection

• US 4,287,599 A
• Filed: 01/22/1979
• Issued: 09/01/1981
• Est. Priority Date: 08/02/1976
• Status: Expired due to Term

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Goncharoff, Nikolai, Puntil, Dennis M.
• Primary Examiner(s): NG, JIN FAY
• Application Number:
  US06/005,544
• Time in Patent Office: 953 Days
• Field of Search: 307/112, 307/113, 307/115, 307/239, 455/76-79, 455/158, 455/160, 455/161, 455/165, 455/166, 455/175
• US Class Current: 455/77
• CPC Class Codes: H03J 5/0281 the digital values being held in an auxiliary non erasable memory
• CPC Class Codes: H03J 7/285 the counter or frequency divider being used in a phase locked loop
• CPC Class Codes: H04B 1/405 with multiple discrete channels

Abstract

A transceiver is disclosed that has a manual scanning electronic channel selection switch with a single actuator that can readily select any one of a predetermined plurality of discrete channels by step tuning the transceiver to each of the discrete channels in either an up or down scanning sequence. An up and down scan actuator is mounted to the housing of the transceiver and another is attached to the microphone of the transceiver, thus providing for remotely tuning the transceiver when access to the transceiver housing is inconvenient. The transceiver is selectively tuned by use of a phase lock loop having a programmable divider that is controlled by a counter which counts clock pulses during up and down scan tuning. An illegal channel detector is provided which prevents the counter from selecting a channel which does not correspond to one of the selectable channels.

The transceiver has apparatus for automatically sequentially scanning a plurality of priority channels and, if signals are received on a scanned channel, producing audible signals related to these received signals, the automatic scanning being temporarily discontinued while priority signals are received. Apparatus for monitoring a nonpriority channel, such as a standard AM broadcast band channel, is also provided.

Apparatus is disclosed which totally prevents any manual or automatic tuning of the transceiver during signal transmission by the transceiver. Every time power is initially supplied to the transceiver, the transceiver will be automatically tuned to a single preselected channel.

Claims

1. A multi-channel communication device operable at a predetermined plurality of discrete priority channel frequencies, the device comprising:

means for receiving signals on a single nonpriority communication channel and producing audible signals in response thereto,

at least one priority channel receiver means tunable in discrete steps for receiving signals on any selected one of a predetermined plurality of discrete priority channels;

means coupled to said priority receiver means for selectively generating, in discrete steps in response to control signals, one of a predetermined plurality of discrete channel signals, each of said channel signals having a different frequency, said one selectively generated channel signal selecting a corresponding one of said priority channels for said priority receiver means;

means, coupled to said generating means, for producing a visual indication identifying the selected channel of said priority receiver means;

automatic tuning means coupled to said generating means for supplying said controls signals thereto for continuously automatically causing said generating means to produce each of said discrete priority channel signals in a predetermined sequence, said automatic tuning means being operative in response to a scan enable signal, said automatic tuning means including automatic scan switch means having a manual actuator with at least a first and second position, said automatic scan switch means producing said scan enable signal in response to a movement of said actuator from said first to second position;

means coupled to said priority receiver means and said automatic tuning means for producing a first inhibit signal for inhibiting further automatic sequencing during the reception of received priority channel signals by said priority receiver means on said one selected priority channel;

means coupled to said nonpriority receiving means and said priority receiver means for interrupting the audible signals related to received nonpriority channel signals and producing audible signals related to received priority channel signals during the reception of signals by said priority receiver means on said one selected priority channel;

manual tuning means coupled to said generating means for manually selecting any one of said plurality of discrete channel signals by supplying said control signals to said generating means;

transmitter means coupled to said generating means for selectively transmitting signals on a selected channel corresponding to the one selected priority channel that said priority receiver means is tuned to, said transmitter means coupled to said priority receiver means for producing a second inhibit signal for inhibiting any manual and automatic priority receiver means tuning whenever said transmitter means transmits signals;

power switch means coupled to said priority receiver means for supplying operative power to said priority receiver means upon actuation of said power switch means; and

first circuit means coupled to said power switch means and said generating means for causing said priority receiver means to be initially tunably controlled by said manual tuning means and to be initially tuned to a preselected one of said priority channels after an actuation of said power switch means, regardless of which priority channel said priority receiver means had last previously been tuned to during any previous actuation of said power switch means, whereby the priority receiver means initially monitors the one preselected channel after actuation of said power switch means and before any manual tuning of said receiver means;

said manual tuning means including first switch means, coupled to said generating means, having a manual actuator with at least a first, second, and third mechanical position, said first switch means providing an up control signal with its actuator in said first position, a down control signal with its actuator in said second position and an enable control signal with its actuator in any one of said first and second positions;

said generating means receiving all of said control signals provided by said first switch means and continuously selectively generating in discrete steps in a first predetermined sequence, each of the discrete channels signals in said predetermined plurality of channel signals as said one channel signal in response to the existence of both said enable and up signals, and continuously selectively generating, in discrete steps in a second predetermined sequence, each said discrete channel signals as said one channel signal in response to the existence of both said enable and down signals, said up and down signals selecting one of said first and second sequences and said enable signal enabling said generating means to selectively generate another of said plurality of different channel signals as said one channel signal, whereby every channel signal is readily selectable by a single actuator causing any one of two distinct channel signal scanning sequences;

said manual tuning means also including a first resistor having magnitude, a first end terminal coupled to a first voltage potential, and a second end terminal, and

a capacitor coupled between said second end terminal and a reference voltage potential,

said first switch means providing a low resistance path substantially less than the magnitude of said first resistor between said second end terminal and a second voltage potential, different from said first voltage potential, in both of said first and second mechanical positions and providing a high resistance path substantially greater than the magnitude of said first resistor between said second end terminal and said second voltage potential with the actuator in its third mechanical position, the voltage at said second end terminal determining said enable signal,

whereby a rapid change in the voltage at said second end terminal is created in response to the actuator being initially moved into said first and second mechanical positions from said third mechanical position and said resistor and said capacitor minimize the effect of switch bounce on the voltage at said second end terminal.

2. A multi-channel communication device operable at a predetermined plurality of discrete channel frequencies, the device comprising:

means for selectively generating, in response to control signals, one of a predetermined plurality of discrete channel signals, each of said channel signals having a different frequency, said one selectively generated channel signal determining the operative channel frequency of said communication device;

means, coupled to said generating means, for producing a visual indication identifying the operative frequency of said communication device; and

first switch means, coupled to said generating means, having a manual actuator with at least a first and second mechanical position, said first switch means providing an up control signal with its actuator in said first position, a down control signal with its actuator in said second position and an enable control signal with its actuator in both said first and second positions;

said generating means receiving all of said control signals provided by said switch means and continuously selectively generating, in discrete steps in a first predetermined sequence, each of the discrete channels signals in said predetermined plurality of channel signals as said one channel signal in response to the existence of both said enable and up signals, and continuously selectively generating, in discrete steps in a second predetermined sequence, each of said discrete channel signals as said one channel signal in response to the existence of both said enable and down signals, said up and down signals selecting one of said first and second sequences and said enable signal enabling said generating means to continuously select different channel signals as said one channel signal, in the sequence selected by said up and down control signals, only as long as said enable signal exists, whereby any of said plurality of channel signals is readily selectable by a single actuator causing any one of two distinct channel signal scanning sequences;

wherein said first switch means includes a bounce eliminator circuit that rapidly creates said enable control signal in response to the movement of said actuator into said first and second mechanical positions, said bounce eliminator circuit comprising;

a first resistor having a magnitude, a first end terminal coupled to a first voltage potential and a second end terminal, and

a capacitor coupled between said second end terminal and a reference voltage potential, and

said first switch means having a third mechanical position for its actuator, said first switch means providing a low resistance path substantially less than the magnitude of said first resistor between said second end terminal and a second voltage potential, different from said first voltage potential, in both of said first and second mechanical positions and providing a high resistance path substantially greater than the magnitude of said first resistor between said second end terminal and said second voltage potential with the actuator in its third mechanical position, the voltage at said second end terminal determining said enable signal,

whereby a rapid change in the voltage at said second end terminal is created in response to the actuator being initially moved into said first and second mechanical positions from said third mechanical position.

3. A multi-channel communication device according to claim 2 wherein said reference voltage potential and said first voltage potential are identical, said capacitor therefore being coupled in parallel with said first resistor.

4. A multi-channel communication device according to claim 3 wherein said actuator includes a contact directly coupled to said second voltage potential, said first switch means comprising a second resistor being coupled between said second end terminal and said actuator contact when said actuator is in said first mechanical position, said resistor being coupled through a diode to the contact of said actuator when said actuator is in said second mechanical position, said diode having anode and cathode terminals, one of which being directly connected to said second resistor and the other being connected to a voltage potential, other than said second voltage potential, through a third resistor, said enable signal being produced at said second end terminal and said up and down control signals being provided at said other terminal of said diode.

5. A multi-channel communication device operable in a plurality of different modes, said communication device comprising:

means for receiving a single nonpriority communication channel and producing audible signals in response thereto,

means for sequentially scanning a receiver over a predetermined plurality of priority communication channels;

means coupled to said priority channel scanning means for inhibiting further priority channel scanning during the reception by said receiver of signals on the one of said priority channels being scanned;

means coupled to said nonpriority receiving means and said scanning priority means for interrupting the audible signals related to said nonpriority channel and producing audible signals related to said received priority channel signals during the reception of said signals by said receiver on the scanned priority channel; and

means including an switch having a manual actuator coupled to said scan inhibiting means for overriding said scan inhibiting means and allowing said scan means to continue its scanning sequence in response to manual actuation of said switch during the reception of priority channel signals on the channel being scanned; and

wherein said scanning means includes a counter having a count that determines the priority channel being scanned, said inhibit means preventing said counter from counting and actuation of said switch changing the count of said counter.

6. A multi-channel communication device operable on a plurality of predetermined channels, said communication device comprising:

at least one receiver means manually tunable by a first manual actuator for receiving signals on any selected one of a predetermined plurality of discrete channels, and receiver means producing audible signals related to the signals received on said selected channel;

means coupled to said receiver means for implementing an automatic scan tuning mode which comprises continuously automatically tuning, in discrete steps, said receiver means to each of said discrete channels in a predetermined sequence, said automatic tuning mode being implemented in response to the existence of a scan enable signal, said automatic tuning means including switch means having a second manual actuator with at least a first and second position, said switch means producing and maintaining said scan enable signal in response to an initial manual movement of said second actuator from said first to second position;

said automatic scan tune mode implementing means including means coupled to said receiver means for automatically producing, as part of said automatic scan tuning mode, a first inhibit signal for temporarily inhibiting, during the existence of said automatic scan tuning mode, further automatic channel tuning during and in response to the reception of a received channel signal by said receiver means of said channel that said receiver means is tuned to and automatically reinstating said automatic scan tuning sequence subsequent to and in response to the termination of the reception of the channel signal; and

transmitter means for selectively transmitting signals on a selected channel corresponding to the selected channel that said receiver means is tuned to, said transmitter means coupled to said receiver means for producing a second inhibit signal for terminating said automatic scan tuning mode in response to actuation of said transmitter means, wherein said automatic scan tuning mode is terminated by said second inhibit signal transmitting said scan enable signal, and subsequent continuous automatic tuning in said automatic scan tuning mode is thereby prevented until said scan enable signal is recreated by again moving said switch means second actuator, whereby the transmission of signals will terminate the automatic scan tuning mode and prevent the automatic resumption of scan tuning thereafter.

7. A multi-channel communication device according to claim 6 which includes means coupled to the switch means of said automatic tuning means for visually indicating by illumination, the existence of said scan enable signal, thereby providing a visual indication of the automatic scan tuning mode of operation of the communication device.

8. A multi-channel communication device according to claim 7 wherein the second actuator of said switch means is normally biased into said first position and constant manual pressure is required to hold said actuator in said second position.

9. A multi-channel communication device according to claim 8 wherein said switch means includes a bistable circuit means that produces and terminates said scan enable signal alternately in response to each movement of said second actuator into said second position.

10. A multi-channel communication device according to claim 9 wherein said bistable circuit means terminates said scan enable signal in response to said transmitter means transmitting signals.

11. A multi-channel communication device according to claim 9 wherein said device has an on-off switch for supplying operative power to said device and said switch means always produces said scan enable signal in response to the first movement of said switch means actuator into said second position after the device receives operative power from said on-off switch.

12. A multi-channel communication device according to claim 9 wherein said bistable circuit means comprises a flip-flop circuit having an output corresponding to said scan enable signal, the output of said flip-flop circuit being alternately set between high and low states in response to each movement of said second actuator into said second position, and said flip-flop always being reset to only one of said high and low states in response to each actuation of said transmitter means.

13. A multi-channel communication device according to claim 12 wherein said second actuator comprises a spring biased pushbutton.

14. A multi-channel communication device according to claim 13 wherein said flip-flop circuit output is always reset to said one of said high and low states in response to actuation of an on-off switch which provides operative power to said communication device, wherein said scan enable signal is produced in response to the first movement of said second actuator into said second position after the communication device receives operative power from said on-off switch.

15. A multi-channel communication device according to claim 6 which includes manual switch means, which comprises said first manual actuator, coupled to said receiver means for manually selecting the channel that said receiver means is tuned to, said first manual actuator with at least a first and second position, movement of said first actuator into one its first and second positions, when automatic tuning is inhibited by said first inhibit signal, causing said receiver means to select a new channel and reinstating said automatic tuning sequence of said receiver means.

16. A multi-chanel communication device according to claim 6 which includes manual switch means including said first manual actuator having a plurality of mechanical positions, said first actuator coupled to said receiver means for manually selecting the channel that said receiver is tuned to, and wherein said automatic tuning means is such that when said automatic tuning means is enabled, the operation of said automatic tuning means is independent of the mechanical positions of said first manual actuator.

18. A multi-channel communication device according to claim 7 wherein said transient circuit includes at least one capacitor and wherein said transient voltages that initially set the count of said counter are created in response to the actuation of said power switch means.

17. A multi-channel communication device comprising:

tunable receiver means for receiving signals on any one of a predetermined plurality of discrete priority channels and producing audible signals in response thereto;

power switch means coupled to said receiver means for supplying operative power to said receiver means upon actuation of said power switch means;

means coupled to said receiver means for manually selectively tuning said receiver means to any one of said priority channels for signal reception by said receiver means to signals on said selected channel; and

first circuit means coupled to said power switch means for causing said receiver means to be subsequently tunably controlled by said manual tuning means but to be initially tuned to a preselected one of said priority channels after an actuation of said switch means, regardless of which priority channel said receiver means had last previously been operatively tuned to during any previous actuation of said power switch means, whereby the receiver means is initially tuned to the one preselected channel after actuation of said power switch means and before any manual tuning of said receiver means and wherein said manually selectively tuning means includes a counter and a manual switch means that selectively supplies said counter with pulses for counting by the counter, said counter coupled to said tunable receiver means and the count of said counter determining the one of said priority channels that said receiver means is tuned to, and wherein said first circuit means comprises a transient circuit coupled between said power switch means and said counter for initially causing the count of said counter to be set to a predetermined count by creating transient voltages in response to changes in the supplying of operative power by said power switch means;

the multi-channel communication device including transmitter apparatus coupled to said counter for selectively transmitting signals on channels which correspond to each of the priority channels that the receiver means is tuned to.

19. A multi-channel communication device comprising:

tunable receiver means for receiving signals on any one of a predetermined plurality of discrete priority channels and producing audible signals in response thereto;

power switch means coupled to said receiver means for supplying operative power to said receiver means upon actuation of said power switch means;

means coupled to said receiver means for manually selectively tuning said receiver means to any one of said priority channels for signal reception by said receiver means to signals on said selected channel;

first circuit means coupled to said power switch means for causing said receiver means to be subsequently tunably controlled by said manual tuning means but to be initially tuned to a preselected one of said priority channels after an actuation of said switch means, regardless of which priority channel said receiver means had last previously been operatively tuned to during any previous actuation of said power switch means, whereby the receiver means is initially tuned to the one preselected channel after actuation of said receiver means; and

wherein said manually selectively tuning means includes a counter and a manual switch means that selectively supplies said counter with pulses for counting by the counter, said counter coupled to said tunable receiver means and the count of said counter determining the one of said priority channels that said receiver means is tuned to; and

second circuit means for intially maintaining the count of said counter after actuation of said power switch means at the count which said counter last had during any previous actuation of said power switch means, and

means for selecting one of said first and second circuit means for determining the initial count of said counter after actuation of said power switch means,

wherein said second circuit means, when selected by said selecting means for determining the count of said counter, comprises structure for continuously providing a voltage to a terminal of said counter regardless of the operative state of said power switch means, and said first circuit means, when selected by said selecting means for determining the count of said counter, comprises structure for creating a transient voltage at said terminal upon said actuation of said power switch means.

20. A multi-channel communication device according to claim 19 wherein at least one of said first and second circuit means includes at least one diode for providing isolation between said first and second circuit means.

21. A multi-channel communication device according to claim 19 wherein said first and second circuit selecting means includes a manual switch having at least two mechanical positions.

22. A manual switch assembly for eliminating switch bounce, said switch assembly adaptable for use in a multi-channel communication device, said switch assembly comprising,

at least one manual switch means having an actuator with at least a first and second mechanical position;

a first resistor having a magnitude, a first end terminal coupled to a first voltage potential and a second end terminal; and

a first capacitor coupled between said second end terminal and a reference voltage potential;

said manual switch means providing a low resistance path substantially less than the magnitude of said first resistor between said second end terminal and a second voltage potential, different from said first voltage potential, with the actuator in said first mechanical position, and said switch means providing a high resistance path substantially greater than the magnitude of said first resistor between said second end terminal and said second voltage potential with the actuator in said second mechanical position, the voltage at said second end terminal being an output control signal of said switch assembly,

whereby a rapid change in the control voltage at said second end terminal is created in response to the actuator being initially moved into said first mechanical position from said second mechanical position and switch bounce which may occur upon movement of the actuator into said second position does not substantially effect the voltage at said second end terminal due to the effect of said first resistor and said first capacitor.

23. A manual switch assembly according to claim 22 wherein said reference voltage potential and said first voltage potential are identical, said capacitor therefore being coupled in parallel with said first resistor.

24. A manual switch assembly according to claim 23 wherein said actuator is normally mechanically biased into said second mechanical position and said actuator requires constant manual pressure to hold said actuator in said first mechanical position.

25. A manual switch assembly according to claim 24 which includes a second capacitor coupled between said second end terminal and said second voltage potential.

26. A manual switch assembly according to claim 25 wherein said second voltage potential is ground.

27. A manual switch assembly according to claim 24 wherein said actuator has a third mechanical position, with constant mechanical pressure being required to hold said actuator in said third position, said switch means providing a low resistance path between said second end terminal and said second voltage potential with said actuator in said third position.

28. A manual switch assembly according to claim 27 wherein said actuator includes a contact directly coupled to said second voltage potential, said manual switch means including a second resistor being coupled between said second end terminal and said actuator contact when said actuator is in said second mechanical position, said resistor being coupled through a diode to the contact of said actuator when said actuator is in said third mechanical position, said diode having anode and cathode terminals, one of which being directly connected to said second resistor and the other being connected to a voltage potential, other than said second voltage potential, through a third resistor, whereby a signal is produced at said second end terminal that indicates movement of the actuator into one of said first and third positions and a signal is created at said other diode terminal which indicates which of said first and third mechanical positions created the signal at said second end terminal:

29. A multi-channel communication device operable on a plurality of predetermined channels, said communication device comprising:

at least one receiver means manually tunable for receiving signals on any selected one of a predetermined plurality of discrete channels, said receiver means producing audible signals related to the signals received on said one selected channel;

means coupled to said receiver means for implementing an automatic scan tuning mode which comprises continuously automatically tuning, in discrete steps, said receiver means to each of said discrete channels in a predetermined sequence, said automatic tuning mode being implemented in response to the existence of a scan enable signal, said automatic tuning means including switch means having a manual actuator with at least a first and second position, said switch means producing and maintaining said scan enable signal in response to an initial movement of said actuator from said first to second position;

said automatic scan tuning mode implementing means including means coupled to said receiver means for automatically producing, as part of said automatic scan tuning mode, a first inhibit signal for temporarily inhibiting, during the existence of said automatic scan tuning mode, further automatic channel tuning during and in response to the reception of a received channel signal by said receiver means on said one selected channel and automatically reinstating said automatic scan tuning sequence subsequent to and in response to the termination of the reception of the channel signal;

means, in addition to said switch means, for selectively terminating said automatic scan tuning mode while maintaining said receiver means operative, regardless of the position of said manual actuator, by terminating said scan enable signal, said scan enable signal remaining terminated until subsequent manual reactuation of said switch means manual actuator recreates said scan enable signal; and

means coupled to the switch means of said automatic tuning means for visually indicating, by illumination, the existence of said scan enable signal, thereby providing a visual indication of the automatic scan tuning mode of operation of the communication device.

30. A multi-channel communication device according to claim 29 wherein the actuator of said switch means is normally biased into said first position and constant manual pressure is required to hold said actuator in said second position.