JPS5856288B2 - wireless transmitter - Google Patents

Description

[Detailed description of the invention] TECHNICAL FIELD The present invention relates to wireless transmitters.

Conventionally, wireless oscillators have driven a high-frequency oscillation circuit at a high voltage to obtain a predetermined oscillation output.
As shown in Figure 1, the DC-
The output of the DC converter 6 was used as a power source for the high frequency oscillation circuit 1, or a high voltage dry battery B2 was used as in 006P (see FIG. 2).

However, these methods have drawbacks such as loss occurring when boosting the power supply voltage, the number of parts, the complexity of the circuit configuration, and the size of the device.

Note that 31 is a modulation circuit, and SW is an operation switch.

The present invention has been made in view of these drawbacks, and its purpose is to be able to display the location even at night using light emitting diodes, and to be able to light up the light emitting diodes even when the storage battery has a low voltage, so that the power source To provide a wireless transmitter that can use a low-voltage storage battery as a battery, save energy by charging with a solar battery, and not increase the size of the device.

The present invention will be described below with reference to an embodiment in which it is applied to a device such as a wireless doorbell.

FIG. 3 shows a circuit diagram of one embodiment, in which a high frequency oscillation circuit 1, a high frequency amplification circuit 2, and a double modulated wave generation circuit 3 consisting of a C-MO8IC are connected to a single cell Ni-Cd storage battery. It is connected to the low voltage storage battery B3.

Storage battery B3 has a solar cell 5 and a diode D.

It is designed to be charged through.

For example, the double modulated wave generation circuit 3 has a frequency of 10KHz or 15KHz.
The modulated frequency signal f1. f2 are sequentially output in the set combination at equal intervals (for example, 13.6 m5ec in the embodiment), and if each interval is 1 bit, both husband and wife's modulated frequency signals f1. A logical value is assigned to f2, and in the embodiment it is a 6-bit serial code signal, and this serial code signal further modulates the oscillation frequency signal of, for example, 260 Mn2 of the high frequency oscillation circuit 1. It is something.

Figure 4a shows the modulation frequency signal f output from point X in Figure 3.
1. FIG. 4 is a diagram showing an example of a combination of f2, and shows a modulated signal at point Y in FIG. 3.

To further explain the double modulated wave generation circuit 3, the double modulated wave generation circuit 3 has, for example, 3.5795M as shown in FIG.
The reference oscillation frequency signal of the Hz crystal oscillator XL is frequency-divided into multiple stages, and the frequency-divided outputs of these multiple stages are outputted from the frequency-divided output terminals O0... of the double modulated wave generation circuit 3, and also at a predetermined frequency. For example, scan signals are sent from the same number of scan output terminals S1 as each divided output terminal 01 at a period of 13.6 m5.
It is designed to rise sequentially at intervals of eC, and by connecting any frequency division output terminal On and scan output terminal Sn, the frequency signal of the frequency division output can be obtained from the oscillation output terminal O8. There is.

Therefore, the frequency signal f1. In order to obtain f2, it is sufficient to connect the scan terminal Sn to the corresponding frequency division output terminal 01 or 02, and in order to obtain the code signal shown in FIG. It is better to connect it to the frequency output terminal 01 or 02.

By connecting the frequency-divided output terminals 01 or 02 to the scan terminal Sn in advance in such a way that a predetermined combination code is obtained, a combined signal string as shown in FIG. It can be used as an identification code.

It goes without saying that the scan time can be set to various values depending on the reference oscillation frequency of the crystal oscillator XL.

Now, when the operation switch SW such as a push button switch is turned on, power is supplied from the storage battery B3 to the double modulated wave generation circuit 3 and the high frequency oscillation circuit 1, and each circuit 3, 1 starts operating, and The modulated frequency signal train of the modulated wave generation circuit 3 is input to the high frequency oscillation circuit 1 to modulate a high frequency signal, and this modulated high frequency signal is amplified by the high frequency amplification circuit 2.
It will be radiated from antenna AN.

FIG. 6 shows another embodiment of the circuit of the present invention, which differs from the circuit in FIG. 3 only in the high frequency amplification circuit 1 including the antenna AN.

FIG. 7 shows a circuit according to another embodiment of the present invention, which differs from the above embodiment in that a lighting display circuit 4 is provided.

The lighting display circuit 4 is for displaying the nighttime position of the wireless transmitter, and includes a current limiting resistor R6 and a light emitting diode LED for display.

A series circuit of resistor R5 is connected to storage battery B3, and current limiting resistor R
A series circuit of a resistor R4 and a capacitor C2 is connected in parallel to the series circuit of 6 and the display light emitting diode LED.
A transistor Q1 is connected in parallel to a series circuit of a capacitor C2 and a resistor R5.

Another transistor Q2 is connected between the base and emitter of this transistor Q1, and further transistor Q1
The base of is connected to the scan terminal S6 of the double modulated wave generation circuit 3 via the resistor R3 and the NC contact of the changeover switch SWo.

In addition, the transistor Q2 has a resistor R2 at its base and emitter, and a diode D and the positive electrode of the solar cell 5.

The base is connected to the connection point of , via a resistor R1.

The changeover switch SWo is interlocked with the operation switch SW, and when the operation switch SW is turned on, the changeover switch SWo changes from the NC terminal to the NO terminal and disconnects the base of the transistor Q1 and the scan terminal S6. .

However, the lighting display circuit 4 configured in this manner operates as follows when the operation switch SW is not operated.

That is, when a scan signal is outputted from the scan terminal S6 as shown in FIG. It is discharged in the closed loop of capacitor C2.

At this time, the voltage at point ■ decreases by the voltage vL determined by resistor R5, current limiting resistor R6, and light emitting diode LED, as shown in Figure 8, and the voltage between ■ and ○ decreases as shown in Figure 8 C. [
vDD+VL], and therefore 1 through the current limiting resistor R6.
Current flows through the light emitting diode LED and the light emitting diode L
The ED will light up.

Here, the voltage waveform across the resistor R6 becomes as shown in FIG. A light emitting diode having a guaranteed lighting voltage can be lit.

Note that the above-mentioned light emitting diode LED is lit only at night; during the day when sufficient sunlight is entering the solar cell 5, the voltage of the solar cell 5 is high enough and the transistor Q2 is turned on. Therefore, even if a scan signal is generated from the scan terminal S6, it is bypassed by the transistor Q2 and the transistor Q1 is kept in an off state, so that the above-mentioned lighting operation is not performed.

Of course, when the amount of sunlight input to the solar cell 5 decreases or disappears, such as at dusk or at night, the voltage of the solar cell 5 decreases, turning off the transistor Q2, and turning off the transistor Q1.
On operation is possible.

Since the present invention has the high frequency amplification circuit as described above, there is no need to obtain the output of the high frequency oscillation circuit with a high power supply voltage.
Therefore, it is possible to use low-voltage storage batteries that are charged by solar cells, and there is no need to use devices with complicated circuit configurations such as DC-DC converters, and there is no need to use bulky batteries, which is inexpensive. It has the effect of being able to be manufactured at a low cost and being miniaturized.In addition, it can be charged by solar cells, which saves energy and requires less maintenance and management, making it very effective for door chimes, etc. A transistor is provided that is driven by a signal periodically output from the wave generation circuit, and a series circuit of a capacitor charged by a storage battery and a resistor is connected in parallel to this transistor, and a lighting guarantee voltage higher than the voltage of the storage battery is applied to the capacitor. Since a lighting display circuit is added in which light-emitting diodes for display are connected in parallel, the lighting of the light-emitting diodes at both ends of the light-emitting diode is guaranteed by periodically driving the transistor and repeatedly charging and discharging the capacitor. It is now possible to generate a voltage that exceeds the voltage, and even if the voltage of the storage battery is lower than the guaranteed lighting voltage of the light emitting diode, the light emitting diode can be lit.
This makes it possible to display information using light emitting diodes without increasing the number of storage batteries, which is very useful in reducing the size of the device.Also, since the transistor is only driven when the voltage of the solar cell is above a predetermined level, The light-emitting diode is turned off during the day, and the position is automatically displayed only at night, which prevents wasted power consumption and is easy to use, as there is no need to forget to turn off the switch when it is blinking with a manual switch. be effective.

[Brief explanation of the drawing]

Figures 1 and 2 are circuit diagrams of conventional examples, Figure 3 is a circuit diagram of an embodiment of the present invention, Figures 4a and b are explanatory diagrams of signal formats used in the above, and Figure 5 is the same as the above. 6 is a circuit diagram of another embodiment of the present invention, FIG. 7 is a circuit diagram of another embodiment of the present invention, and FIGS. 8a to 8d are the same as above. 1 is a high-frequency oscillation circuit, 2 is a high-frequency amplification circuit, 3 is a double modulation wave generation circuit, 4 is a display lighting circuit, 5 is a solar cell, R3 is a storage battery, C2 is a capacitor, and LED is Light emitting diode for display, R5 is a resistor, Ql
is a transistor.

Claims (1)

[Claims] 1. In a wireless oscillator whose power source is a low-voltage storage battery charged by a solar cell, a transistor is driven by a signal periodically output from a modulated wave generation circuit and turns off when the voltage of the solar cell exceeds a predetermined level. A series circuit consisting of a capacitor charged by a storage battery and a resistor is connected in parallel to this transistor, and a lighting display circuit is added in which a light emitting diode for display with a guaranteed lighting voltage higher than the voltage of the storage battery is connected in parallel to the capacitor. A wireless transmitter characterized by comprising: