JPS6333932A - Radio talking equipment - Google Patents

Abstract

PURPOSE:To prevent defective operation due to battery wear in advance by providing a battery wear notice signal generating circuit and a means sending an audible signal to an opposite talking equipment by its output at talking to a trasmission circuit section. CONSTITUTION:If a power voltage Vcc drops below a prescribed value, a voltage divided value by resistors R2, R3 is lower than a reference voltage VR and an output of a comparator IC1 goes to H level via a resistor R4. On the other hand, an oscillation circuit comprising the inverter constitution of NAND circuits IC3, IC2 oscillates an optional audible frequency decided by resistors R5, R6 and a capacitor C1. The NAND circuit IC4 outputs a signal having a frequency decided by the oscillation circuit when the output of the comparator IC1 is at H level by the inputs. The output of the NAND circuit IC4 is smoothed by the resistor R7 and the capacitor C2 and inputted to a modulation amplifier circuit 2 via a resistor R8 and sent with FM modulation. Then the opposite party receives and demodulates it the same as voice signal and the result is outputted from a speaker so as to confirm the drop of the battery voltage of the sender side.

Description

[Detailed description of the invention] 【Technical field】

The present invention relates to a wireless communication device used as an intercom or the like in homes or offices.

[Background technology]

In recent years, the development of HALFI devices has been remarkable, and in particular, wireless devices such as cordless telephones and cordless intercoms are increasingly being used in homes and offices as voice transmission means. Furthermore, due to the effectiveness of wireless technology, most of these devices are powered by batteries (using storage batteries or dry batteries). However, when such a wireless communication device is used, for example, as a doorbell, it is necessary to be able to check the battery status of the indoor (parent) device and the outdoor (child) device, but conventionally such a function has not been provided. However, there was a problem in that the telephone call function was not available when necessary.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a wireless communication device that can check the voltage status of the communication device to ensure that it is always in a normal operating state without requiring any special checking operation. .

[Disclosure of the invention]

LLL FIG. 1 is a block diagram of the entire circuit of one of the telephone sets according to the first embodiment of the present invention, and FIG. 2 is a circuit diagram of the main circuit of the same. A carrier wave signal generated from a high frequency oscillation circuit 1 is input to a modulation amplification circuit 2, and is FM-modulated by a signal obtained by amplifying an audio signal from three microphones by an AF amplifier 4. The output of this modulation amplification circuit 2 is amplified by a high frequency amplification circuit 5 and then transmitted via a duplexer 6 and an antenna 7. On the other hand, a radio signal for reception with a frequency different from the transmission frequency is received via the antenna 7 and the duplexer 6, inputted to the mixer circuit 9 via the high frequency amplifier circuit 8, and output from the high frequency oscillation circuit 1. The intermediate frequency signal obtained by mixing is input to the demodulation circuit 10. The low frequency audio signal demodulated by the demodulation circuit 10 drives the speaker 12 via the AP amplifier 11. Next, the battery exhaustion notice signal oscillator circuit 13 according to the present invention constantly checks the voltage state of the battery 15 for powering the handset, and when the battery 15 voltage Vcc falls below a predetermined voltage, the audible frequency The signal is input to the modulation amplification circuit 2, and is configured to be transmitted as an audible signal to the other party's communication device during a conversation using the microphone 3. FIG. 2 shows a circuit example of the above-mentioned battery exhaustion warning signal oscillation circuit 13, and the circuit according to the embodiment shown in FIG. 2 will be described below. Now, when the power supply voltage Vcc from the battery 15 is above a predetermined value, the voltage division value of the power supply voltage by the resistors R2 and R5 is set higher than the reference voltage ■R determined by the current limiting resistor R and the Zener diode Dz. Comparator IC
, is at the "L" level. Therefore, NAND circuit I
The output of C is at the 'H°' level, and no signal is output. When the voltage Vcc of the 0th power supply falls below a predetermined value, the voltage divided by the resistors R2 and R5 becomes lower than the reference voltage ■R. , the output of comparator I C+ is resistor R1
It becomes "H" level through. On the other hand, Nantes circuit IC2,
The oscillation circuit consisting of an inverter configuration of IC, has a resistor R1
, R6 is configured to oscillate at an arbitrary audio frequency determined by the capacitor CI. Thus, by these inputs, the NAND circuit IC1 outputs a signal of the frequency determined by the oscillation circuit when the output of the comparator IC is at the "H" level. The output of this NAND circuit IC is smoothed by a resistor R7 and a capacitor C2, and then is smoothed by a resistor R3.
The signal is input to the modulation amplification circuit 2 via FM, and is FM-modulated and transmitted. Then, on the other party's side, this signal is received and demodulated in the same way as an audio signal and output from a speaker, so that it is possible to confirm a drop in the battery voltage on the transmitting side. Figure 3 shows a block diagram of one of the telephone sets according to the second embodiment of the present invention. A detection signal generation circuit 14 is provided, and this battery voltage detection signal generation circuit 14 monitors the voltage VCC of the battery 15.
When the call button 16 is pressed, when a confirmation sound is generated via the speaker 12 to confirm to the operator that the call button 16 has been pressed, the frequency of this confirmation sound is set to the voltage of the battery 15. It is designed to change depending on Vcc. FIG. 4 shows a specific example of the above-mentioned battery voltage detection signal generation circuit 14. In the circuit of FIG.
When is pressed, current flows through resistors R5 and R2, and passes through transistor Tr to comparator IC1 and inverter IC2.
, the power supply voltage is applied to the frequency dividing circuit 17 and the like. Then, the VCO (voltage controlled oscillator circuit) consisting of inverter IC2, coil L, capacitors C+, Cz, and varicap diode DF starts oscillating.This oscillation frequency is the value obtained by dividing the power supply voltage ■cc by resistors R2 and R3. changes in accordance with the capacitance change of the varicap diode Dy, whose output is impedance-converted by a voltage follower circuit composed of a comparator IC+ and biased through a resistor Rs.Now, for example, when the power supply voltage decreases, the varicap diode The bias voltage of the DF decreases, and its capacitance increases due to the reverse bias voltage/capacitance characteristics as shown in Figure 6, and the power supply voltage/oscillation frequency characteristics as shown in Figure 7 cause the above-mentioned
The oscillation frequency of CO decreases. Thus, the output of this oscillation frequency is converted to an arbitrary audible frequency by operating the transistor Tr2 via the frequency dividing circuit 17, and the speaker 12 broadcasts the frequency sound. In other words, as shown in Figure 5(a), when the power supply voltage Vcc is initially high, a relatively high frequency sound (for example, IKHz) is a "beep", but as the power supply voltage Vcc decreases, the sound changes to the same level as that shown in Figure 5(b). ), the frequency decreases (for example, 500 Hz) and becomes a "boo". When the other party calls in this way, when the call button 16 is pressed, a sound that follows the power supply voltage value is announced, and the battery 1
5, it is possible to judge whether the situation is bad or not, and this notification sound also serves as an operation confirmation sound. The call button 16 is operated when calling the other party, and is reset once the call is started. [Effects of the Invention] Since the present invention is configured as described above, it is possible to check the power supply voltage of the battery power supply, etc. every time a call is made, and it is possible to prevent malfunctions due to battery exhaustion. It has the effect of not causing inconveniences such as inoperability when necessary, and does not require any special operation to check the voltage of the battery power supply, so there are no inconveniences such as forgetting to perform a check. It has an effect that will never occur.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a telephone according to a first embodiment of the present invention;
Fig. 2 is a circuit diagram of the battery exhaustion notice signal generation circuit same as above, Fig. 3 is a block diagram of a telephone handset according to the second embodiment of the present invention, and Fig. 4 is a circuit diagram of the battery voltage detection signal generation circuit same as above. , Figures 5(a) and 5(b) are diagrams of example signals generated when the power supply voltage is high and low, respectively, Figure 6 is a reverse bias capacitance characteristic diagram of a varicap diode, and Figure 7 is a diagram of VCO
3 is a power supply voltage/oscillation frequency characteristic diagram, 3 is a microphone, 6 is a
1 is a branching filter, 7 is an antenna, 12 is a speaker, 13 is a battery exhaustion notice signal generation circuit, and 14 is a battery voltage detection signal generation circuit. Agent Patent Attorney Ishi 1) Chief 70, Ω 0 (committee)

Claims (2)

[Claims] (1) A transmitting circuit that modulates a high frequency signal with an audio signal input from a microphone and transmits it from an antenna via a duplexer, and a radio signal with a frequency different from the transmitting frequency to the antenna and duplexer. A wireless communication system in which a pair of communication devices each having a receiver circuit unit that receives an audio signal through the communication terminal and drives a speaker with a demodulated audio signal is provided, and the transmission frequency of one communication device becomes the reception frequency of the other communication device. In the device, the transmitting circuit includes a battery-out notice signal generating circuit that generates a signal when the battery voltage of the above-mentioned handset falls below a predetermined value, and an output from the battery-dead notice generating circuit causes the other party's handset to be activated during a call. 1. A wireless communication device comprising: a means for transmitting an audible signal to a wireless communication device; (2) A transmitting circuit section that modulates a high frequency signal with an audio signal input from a microphone and transmits it from the antenna via a duplexer, and a radio signal of a frequency different from the transmitting frequency to the antenna and duplexer. A wireless communication system in which a pair of communication devices each having a receiver circuit unit that receives an audio signal through the communication terminal and drives a speaker with a demodulated audio signal is provided, and the transmission frequency of one communication device becomes the reception frequency of the other communication device. 1. A wireless communication device, characterized in that the device is provided with a battery voltage detection signal generation circuit that generates a confirmation tone at a frequency that follows the power supply voltage of the communication device when the other party calls.