Abstract: A walkie-talkie device applies a continuous tone-coded squelch system (CTCSS) to control signal transmission. The walkie-talkie device has an analog-to-digital converter, a digital signal processor, and a digital-to-analog converter. The signal processing method includes using the analog-to-digital converter to convert a first analog signal into a first digital signal, using the digital signal processor to handle a CTCSS tone related to the first digital signal for generating a second digital signal, and using the digital-to-analog converter to convert the second digital signal into a second analog signal. The walkie-talkie device uses the CTCSS tone to discriminate a required speech signal from other speech signals transmitted by the same physical channel.

Abstract: A method of eliminating irritating noise at the end of communication for a walkie-talkie which has a receiving loop. The method includes providing a first detector, determining whether a radio frequency signal in a predetermined frequency range received by the walkie-talkie belongs to a non-standard squelch signal by using the first detector, and if so, stopping the walkie-talkie from receiving subsequent radio frequency signals.

Abstract: A walkie-talkie set includes a first walkie-talkie and a second walkie-talkie. The first walkie-talkie includes a user interface having a push-to-talk button and a microphone for receiving voice signals when the button is depressed, a processor, and a transceiver for emitting a control signal generated by the processor and the voice signals received from the microphone. The second walkie-talkie includes a casing, a transceiver, and a vibration motor for vibrating the casing when receiving the control signal from the first walkie-talkie.

Abstract: A method of generating a warning signal for a walkie-talkie includes: providing a detector and a timer; using the timer to count time; using the detector to determine whether the strength of a radio frequency (RF) signal which includes a standard CTCSS tone received by the walkie-talkie is larger than a predetermined value; using the detector to determine whether the strength of a RF signal which includes a non-standard CTCSS tone received by the walkie-talkie is larger than the predetermined value; if so, resetting the timer; and issuing a warning signal when the time counted by timer reaches a predetermined time.

Abstract: A method of generating a warning signal for a walkie-talkie includes: providing a detector and a timer; using the timer to count time; using the detector to determine whether the strength of a radio frequency (RF) signal which includes a standard CTCSS tone received by the walkie-talkie is larger than a predetermined value; using the detector to determine whether the strength of a RF signal which includes a non-standard CTCSS tone received by the walkie-talkie is larger than the predetermined value; if so, resetting the timer; and issuing a warning signal when the time counted by timer reaches a predetermined time.

Abstract: A walkie-talkie device applies a continuous tone-coded squelch system (CTCSS) to control signal transmission. The walkie-talkie device has an analog-to-digital converter, a digital signal processor, and a digital-to-analog converter. The signal processing method includes using the analog-to-digital converter to convert a first analog signal into a first digital signal, using the digital signal processor to handle a CTCSS tone related to the first digital signal for generating a second digital signal, and using the digital-to-analog converter to convert the second digital signal into a second analog signal. The walkie-talkie device uses the CTCSS tone to discriminate a required speech signal from other speech signals transmitted by the same physical channel.

Abstract: A microprocessor uses an interrupt signal for terminating a power-down mode, and a method thereof is used for controlling a clock signal related to the power-down mode. The microprocessor has a clock control unit for controlling whether a clock signal is outputted from a clock generator to the microprocessor, a first control unit which outputs a first control signal to the clock control unit when being level-triggered by an interrupt signal, and a second control unit which outputs a second control signal to the clock control unit for activating a power-down mode. The method includes (a) generating the second control signal to stop the clock generator from outputting the clock signal to the microprocessor, and (b) generating the interrupt signal to trigger the corresponding first control signal for terminating the power-down mode and actuating the clock generator to output the clock signal to the microprocessor after performing step (a).

Abstract: A microprocessor uses an interrupt signal for terminating a power-down mode, and a method thereof is used for controlling a clock signal related to the power-down mode. The microprocessor has a clock control unit for controlling whether a clock signal is outputted from a clock generator to the microprocessor, a first control unit which outputs a first control signal to the clock control unit when being level-triggered by an interrupt signal, and a second control unit which outputs a second control signal to the clock control unit for activating a power-down mode. The method includes (a) generating the second control signal to stop the clock generator from outputting the clock signal to the microprocessor, and (b) generating the interrupt signal to trigger the corresponding first control signal for terminating the power-down mode and actuating the clock generator to output the clock signal to the microprocessor after performing step (a).