JPS6098733A - Malfunction preventing circuit - Google Patents

Abstract

PURPOSE:To prevent an unnecessary radio wave from being transmitted by allowing a malfunction preventing circuit to detect the pressing state of a microphone press switch, detecting a transmission output from a radio section and to disconnect the power supply to the radio section. CONSTITUTION:The malfunction preventing circuit 4 detecting a transmission output from the radio section 2 is provided to control the radio section 2 to operating and inoperating state based on the output of the circuit 4. Thus, the transmission output at fault from the radio section 2 is stopped to prevent an unnecessary radio wave from being transmitted.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a malfunction prevention circuit for a radio device, such as a personal radio device, which uses a microphone with a 100-degree angle.

In a conventional radio device, as shown in FIG. 1, a press switch 1 and a radio section 2 are directly connected without going through a microcomputer. However, in a non-P:Jt I system using a micro combi coater, for example, in a personal radio, as shown in FIG. The eX is configured such that the microcomputer 3 outputs a press signal to the wireless section 2. Therefore, if the microcomputer 3 malfunctions due to a cause such as runaway of the microcomputer 3 or stoppage of clock oscillation, the press signal will be output from the microcomputer 3 even though the microphone press switch 1 is not in the on state. As a result, there is a risk that a 'JIT' situation may occur in which unnecessary transmission output (radio waves) is generated from the wireless section 2.

However, the present invention provides a malfunction prevention circuit to solve such a situation. A second detection means for detecting the transmission output, a logic means driven by both cylinders 183 and the second detection means, and a power supply means for cutting off and covering power to the wireless section based on the logic means. It is composed of

FIG. 3 shows the basic configuration of the present invention. This basic configuration is the same as the conventional non-LFJ machine: 1. In addition to the radio, a malfunction prevention circuit 4 is added that detects the pressed state (on/off) of the microphone press switch 1 and also detects the transmission output from the wireless section 2, and based on the output of this malfunction prevention circuit 4, The wireless unit 2 is controlled to be in an active state or a non-active state. In other words, the malfunction prevention circuit 4- does not particularly operate when the microphone press switch 1 is on and there is a transmission output from the wireless section 2, but when the microphone press switch 1 is on and the wireless When there is a transmission output from section 2, it operates to put radio section 2 into a non-operational state.

Next, a circuit diagram of the malfunction prevention circuit 40 is shown in FIG. 4, and will be described in further detail.

The power supply 5 is connected to the emitter of the h-transistor Q1 through the resistor R1, and the two transistors of the h-transistor Q1 are connected to the terminal T1 which leads to the drive stage of the transmitting part of the radio part 2 and the antenna switching circuit (all of which are not shown). It is connected. Therefore, the supply of power 5 to the radio unit 2 is controlled by turning on and off the transistor Q1. 1~Ran resistor Q
A resistor R2 is connected between the emitter and the base of the transistor Q1, and the base of the transistor Q1 is connected between the resistor R3.1 and the run lister Q.
The base of the transistor Q2 is connected to the output terminal OU of the NAND circuit 6 via the resistor R4.
Connected to T.

The NAND circuit 6 may be any suitable circuit, but in this case it is a transistor Q3, diodes [)1, [)2.

D3 and resistors R5 and R6.

In this NAND circuit 6, the collector of the transistor Q3 whose emitter is grounded is connected to the output terminal 0tJT, and the cathode of the diode D1 is connected to the first input terminal 11).
1, and the cathode of the diode D2 is connected to the second input terminal 1n2. The power supply 5 is connected via a resistor R5 to the collector of the transistor Q3, while via a resistor R6 to the respective anodes of the diodes Di, D2, l)3. Further, the base of transistor Q3 is connected to the cathode of diode D3. The first input terminal 1111 of the NAND circuit 6 is connected to the other end of the microphone press switch 1 whose one end is grounded, and its second input terminal is connected to the mic press switch 1 whose emitter is grounded.
It is connected to the collector of transistor Q4.

The microcomputer 3 originally has various functions, but since these functions are not directly related to the present invention, a description thereof will be omitted. The input side of the microcomputer 3 is connected to the other end of the microphone press switch 1, and detects the pressed state of the microphone press switch 1, that is, whether it is on or off.

Further, the output side of the microcomputer 3 is connected to the emitter of the transistor Q2, and is configured to output a press signal at least when the microphone press switch 1 is in the on state.

On the other hand, the base of the transistor Q4 is connected via a resistor R1 to the collector of a transistor Q5 whose emitter is grounded. Also, the collector of transistor Q5 is connected to resistor R
8 to the power supply 5 while the required display circuit 7
It is also connected.

Furthermore, the base of transistor Q5 is connected to the other end of microphone press switch 1 via collector J3 and emitter of transistor Q6. Also, transistor Q
The base of 6 is connected to the power supply 5 via a resistor R9.

1. Connected to a circuit (not shown) for detecting the transmission output of the final stage of the transmitting section of the radio section 2; :Terminal T2 is connected to voltage doubler rectifier circuit 8 via converter C2. Further, the 1a voltage rectifier circuit 8 is connected to a time constant circuit 9, and the time constant circuit 9 is a transistor. It is connected to the base of 5.

Consists of diode D4, os and capacitor c3 (B voltage rectifier circuit 8, resistor RIO and capacitor c3)
The cathode of the diode D4, whose anode is grounded, is connected to the capacitor C4 in the previous stage.
The other end of the diode D5 is connected to the anode of the diode D5, the cathode of the diode D5 is grounded via the capacitor C3, and connected to one end of the resistor R10, and the other end of the resistor R10 is grounded via the capacitor C4 and connected to the transistor. . It is grounded to the base of 5. In addition, when the microphone press switch is turned on, the AT IS signal is automatically emitted every 1 minute when the microphone press switch is turned on, and at the same time as A).
Regardless of the press state of the microphone press switch 1, approximately 0.0.
The transmission output may be sent for 2 seconds. Therefore, in order to judge that this 0.2 seconds is normal operation, the resistor R10 of the time constant circuit 1o and the converter C4 are used to
．． Make up 2 seconds.

With J3 in this circuit configuration, when the microphone press switch 1 is turned on, the first input terminal 1111 of the NAND circuit 6 is grounded ("low" state) via the microphone press switch 1. Therefore, the 1-run lister Q3 is turned off, and the output terminal OjJT of the NAND circuit 6 becomes "
becomes “high” state. Therefore, since the pressure signal 18 from the micronbutton 3 is input to the collector of the transistor Q2, the transistor Q2 becomes conductive.

When transistor Q2 becomes conductive, it becomes a transistor. 1b becomes conductive, and the power source 5 is supplied to the drive stage of the transmitting section of the radio section 2 and the antenna switching circuit via the resistor R1 and the emitter of the transistor Q1. On the other hand, the transmission output detection signal from the final stage of the transmitting section of the radio section 2 is input to the voltage doubler rectifier circuit 8 via the converter C2, where it is rectified. Next, the capacitor C4 of the time constant circuit 9 is charged by the rectified output, but since the emitter of the transistor Q6 is grounded by the microphone press switch 1 and the transistor Q6 is conductive, the condenser C4 is charged by the microphone press switch 1. As long as the press switch 1 is in the on state, the discharge state is maintained. Therefore, transistor Q
5 becomes non-conductive, and transistor Q4 becomes conductive.

Therefore, the second input j terminal of the NAND circuit 6 is in the "low" state, and its output p terminal OUT- continues in the "high" state.

Next, an abnormality occurred in the microcomputer 3 even though the microphone press switch 1 was not on.
A case will be described in which a transmission output is being sent from the wireless section 2. Similarly to the above, the transmission output detection signal from the final stage of the transmitting section of the radio section 2 is rectified by the voltage doubler rectifier circuit 8, and charges the capacitor C4 of the time constant circuit 9. It continues even after the time set by the time constant circuit 9, here 0.2 seconds. (When the transmission output detection signal is input, the transistor Q6 is in a non-conductive state,
is conductive. When the transistor Q5 becomes conductive, the transistor Q4 becomes non-conductive, and the second input terminal I"12 of the NAND circuit 6 becomes in a "high" state. On the other hand, since the first input terminal 1111 of the NAND circuit 6 is in a "high" state, the transistor Q3 is conductive, and the output terminal 0LJT of the NAND circuit 6 is in a "low" state. After the IC,
Transistor Q2 due to an error in microcomputer 3
Even if a press signal is output to the emitter of the transistor 02, the transistor 02 will not become conductive. Therefore, (- the run lister Q1 becomes non-conductive, and the driving stage L of the transmitting section of the radio section 2
The power supply 5 is cut off to the antenna switching circuit 13 and the antenna switching circuit, thereby preventing the transmission output from leaving the transmitting section of the radio section 2 due to an abnormality in the microcomputer 3.

It should be noted that when such an abnormality occurs, the input level to the display circuit 7 changes from a "high" state to a "low" state, and based on this change, an indication to that effect is provided by, for example, a light emitting diode.

As mentioned above, in the present invention, the malfunction prevention circuit detects the pressed state of the microphone press switch and detects the transmission output from the wireless section, and upon detection of both, cuts off the power supply to the wireless section. This configuration has the advantage that abnormal transmission output from the radio section can be stopped and unnecessary transmission of radio waves can be prevented. Although the present invention describes the prevention of transmission output from the wireless unit due to an abnormality in the microcomputer, the same applies to abnormal oscillations in the transmitter itself of the wireless unit, such as in the drive stage or the final stage. It is preventable.

[Brief explanation of the drawings] Figures 1 and 2 are block diagrams of conventional examples;
The figure is a block diagram showing the basic configuration of the present invention, and FIG. 4 is a wiring diagram of the malfunction prevention circuit according to the present invention. In the figure, 1... microphone press switch, 2... radio section, 3... microcomputer, 4... malfunction prevention circuit, 5... power supply, 6... NAND circuit, 7...・
Display circuit, 8... voltage doubler rectifier circuit, 9... time constant circuit. Special consideration applicant General Co., Ltd.

Claims (5)

[Claims] (1) The microcomputer detects the press state of the microphone press switch, and at least when the microphone press switch is on, the microcomputer outputs a press signal to the radio section to return the radio section to the operating state. This malfunction prevention circuit disables the radio section when there is a transmission output from the radio section even though the microphone press switch is in the on state and tT in the radio set. (2) A first detection means that detects the pressed state of the microphone press switch within the specified range (1), and a second detection means that detects the transmission output of the wireless section. and 83 driven by both cylinders 1 and the second detection means.
! A malfunction prevention circuit includes a 11th stage and a power supply means for cutting off power to the wireless section based on logic means. (3) A malfunction prevention circuit according to claim (2), characterized in that the second detection means includes a rectifier circuit and a time constant circuit. (4) Claim (2) - A malfunction prevention circuit characterized in that the C1 logic means is a NAND circuit. (5) Patent' [Claim (2), a malfunction prevention circuit in which the first detection means is provided with a display means activated by a click.