JPS62258594A - Rain drop sound mixing circuit - Google Patents

Abstract

PURPOSE:To prevent the crosstalk of an audio stereo signal by using a diode to mix a monaural signal with an audio stereo signal from a rain drop sound generating circuit using a PUT. CONSTITUTION:An audio circuit has a right side audio circuit and a left side audio circuit, and the right side audio circuit includes a right side signal mixing resistance circuit MIX(R) including a terminal J(R) and the left side audio circuit includes a left signal mixing resistance circuit MIX(L) including a jack terminal J(L). Diodes D6, D7 are inserted respectively between the cathode of a PUTQ1 and the two mixing resistance cirucits MIX and the diodes D6, D7 give reverse bias to the audio signal. Thus, the left side audio signal and the right side audio signal are not interferred together via the rain drop sound generating circuit and the left/right channel crosstalk is prevented.

Description

TECHNICAL FIELD The present invention relates to a raindrop sound mixing circuit that mixes a raindrop sound signal that induces sleep and an audio stereo signal.

(b1 Summary of the Invention This invention mixes the oscillation output of a relaxation oscillation circuit using a PUT into an audio stereo signal by branching the relaxation oscillation output into two circuits using two diodes, and in each circuit, the right side signal and the left side signal are mixed. The signal and relaxation oscillation output are kept warm.

(C) Prior art and its drawbacks As a raindrop sound generating circuit, conventional technology
Disclosed in the issue. This conventional device consists of a discharge tube and a CR
It is composed of a combination of.

However, such a configuration has the disadvantage that it is difficult to miniaturize, and furthermore, as long as a discharge tube is used, there is a limit to low voltage driving. Furthermore, since this raindrop sound generating circuit uses a discharge tube, it is difficult to mix the raindrop sound signal with a general audio stereo signal.

(d1 Purpose of the Invention The purpose of this invention is to use PUT instead of a discharge tube to enable miniaturization and lower voltage, and to generate monaural signals and audio stereo signals from a raindrop sound generation circuit using PUT. An object of the present invention is to provide a pre-raindrop mixing circuit that can prevent crosstalk of audio stereo signals by using diodes for mixing.

(e) Structure and Effects of the Invention The present invention provides a circuit for mixing an oscillation output of a relaxation oscillation circuit configured with a PUT as a switching element into an arbitrary audio stereo signal. Two diodes were connected in such a direction that the oscillation output polarity was forward polarity, and a right signal mixing resistor circuit and a left signal mixing resistor circuit were connected to the non-relaxation oscillation circuit side of each of the two diodes. It is characterized by

According to the present invention, by configuring as described above,
Since the PUT is used to perform relaxation oscillation, low voltage driving is possible, and a small battery of several volts can be used. In addition, the relaxation oscillation output terminal is set to have a forward polarity.
Since we connected two diodes to each of the two diodes and connected a right-side signal mixing resistor circuit and a left-side signal mixing resistor circuit to each of the two diodes, when viewed from the stereo signal circuit, the diodes described above are equivalently infinite. Because of the resistance, the raindrop sound signal is properly mixed with the stereo left and right signals, but the stereo left and right signals do not interfere with each other via the raindrop sound generation circuit.

Therefore, even without a switch to switch between a monaural circuit (raindrop sound generation circuit) and a stereo circuit (audio stereo circuit), it is possible to pass only the audio stereo signal through the mixing circuit without causing any crosstalk. Also, only the monaural signal (raindrop sound signal) can be passed through the mixing circuit as is. That is, the present invention has the effect that a switch for switching between a monaural circuit (raindrop sound generation circuit) and a stereo circuit (audio stereo circuit) is not required, and there is no crosstalk between audio stereo signals via the mixing circuit. .

(fl Example) As an example of the present invention, an electronic cooling/warming pillow using a raindrop sound generating circuit is shown. Regarding an electronic cooling/warming pillow using a Peltier element, for example, Utility Model Application No. 60-59255.2925
6.59433.59434, Jitsugan Sho 61-40208
It is suggested in the issue etc. This electronic cooling/heating pillow is equipped with an electronic cooling/heating device including a Peltier element in the pile main body, the cooling surface of this electronic cooling/heating device is arranged on one flat surface of the pile main body, and a heat dissipation fin and a fin cover are installed on the pile main body. It is placed on one shoulder. Since the Peltier element itself is not very large, a mat containing, for example, glue and sodium chloride is placed on the cooling surface of the pile body.
A metal plate with good thermal conductivity, such as aluminum, is provided at the bottom of this mat, extending from the cooling part of the Peltier element.

Further, the radiation fins are also composed of a plurality of fins made of aluminum, and a fin cover is provided around the fins. When an electronic heating/cooling pillow having such a configuration is placed with the cooling surface facing upward, the back of the head rests on the cooling surface and the entire head is cooled. Furthermore, if the pile main body is arranged so that the cooling surface is located downward, the radiation fins will be located from the lower part of the head to the shoulders, and the area from the shoulders to the head will be warmed.

With electronic heating and cooling pillows, you can simply change the position of the pillow in this way.
It can be used as a cold pillow or a warm pillow without using a changeover switch.

(Completed on 11th) Structure of cooling/warming pillow FIG. 3 is an exploded view of an electronic cooling/warming pillow having a raindrop sound generating circuit according to an embodiment of the present invention, and FIG. 4 is a completed view thereof.

In FIG. 3, the pile main body 10 is made of urethane foam material and is formed entirely into a rectangular parallelepiped shape as shown in the figure.

On one flat surface 10a of the pile body 10, a relatively large recess 10c is formed slightly closer to the front end surface 10b, and a recess 10e in which a radiation fin, which will be described later, is housed is formed closer to the rear end surface 10d. The electronic cooling/heating device 11 includes a Peltier element, a cooling plate 11a made of aluminum, a heat radiation fin llb also made of aluminum, and a heat radiation fin lb made of aluminum.
It is composed of a fin cover 11c that covers the cooling plate 11a, and a mat lid that is placed on the cooling plate 11a. The mantle lid contains seaweed and sodium chloride,
The entire cloak is cooled by being cooled by the cooling plate 11a.

FIG. 5 shows the main parts of the electronic heating and cooling device. Reference numeral 11e denotes a Peltier element, the cooling plate 11a is fixed to this cooling part, and the heat radiation fin 11b is fixed to the heat radiation part.

A sound generating section 12 is attached to both ends of the radiation fin 11b. This sound generating section 12 is a speaker 12b
This speaker 12b is fixed, and an opening 12d is made in the center.
The speaker mounting plate 12a includes a speaker mounting plate 12a having a circular shape, and a sealing member 12C that covers the circumference of the circular speaker 12b. The sealing member 12c is made of hard urethane foam,
It is attached to the speaker mounting plate 12a.

FIG. 7 is a diagram showing the installed state of this sound generating section. As shown in the figure, the front surface of the speaker 12b is directly connected to the heat radiation fin llb through the opening 12d of the speaker mounting plate 12a.
, and the rear surface of the speaker 12b is the pile body 10a.
The positional relationship is opposite to . Furthermore, the periphery of the speaker 12b is sealed by a sealing member 12c. Due to this structure, the sound from the rear side of the speaker 12b is absorbed by the pile main body 10a and the urethane foam of the sealing member 12c, and a panfuru effect can be obtained as a kind of sealed box. Furthermore, since the sound emitted from the front of the speaker is reflected by the radiation fin llb, it is possible to obtain a reflection and diffusion effect of mid-high range sound. Therefore, even if the speaker 12b is thin and small, it is possible to achieve high-fidelity sound with extended low and high frequencies. Since each speaker is provided independently, the two speakers can be used as stereo speakers.

In the electronic heating/cooling pillow configured as described above, as shown in FIG. 4, the mat lid serving as a cooling surface is located on one side of the pile body 10a, and the radiation fins Ilb and their fin covers 11c are located on one side of the pile body 10a. Located on one shoulder. Therefore, if the pile main body 10a is set so that the pine l-11d is positioned upward as shown in the figure, the back of the head will be exactly
Since it is located at the id position, it can be used as a cold pillow. FIG. 6 shows this situation. The device is shown when being used as a cold pillow. At this time, the mat 1 used as a cooling surface is located above the pile body 2. Reference numeral 3 denotes a radiation fin, and when the mat 1 is positioned above, a right speaker 4R is arranged at the left end of the radiation fin 3, and a left speaker 4L is arranged at the right end. Therefore, the left speaker 4L is located on the left ear side, and the right speaker 4R is located on the right ear side.
is located.

FIG. 6(B) shows the state when used as a warming pillow. When switching from a cold pillow to a warm pillow, the pile body 2 is rotated 180 degrees in the direction of arrow A in the figure. When the pile body 2 is rotated by 180 degrees as shown in the figure, the mat 1 is positioned below the pile body 2, and the radiation fins 3 are positioned below the back of the head and shoulders of the person 5. Since the pile main body 2 only needs to be rotated by 180 degrees in the direction of the arrow A, the right speaker 4R is located on the same right side when the person 5 is centered. Similarly, left speaker 4
L is also located on the left side. Therefore, whether it is used as a cold pillow or a warm pillow, the right speaker will be located on the right side, and the left speaker will be located on the left side. In other words, there is no need to switch the polarity of the speaker when used as a cold pillow and when used as a warm pillow. Figure 6 FC1 shows the case where the person 5 is listening to stereo while awake. The pile body 2 is attached to the 6th
When used as a cold pillow shown in the figure, it rotates 180 degrees in the direction of arrow B in a plane. In this operation, as is clear from the figure, the speakers 4R:4L become closer to humans, and the speaker 4R14L is located at the upper part of the pile body 2, so that the listening position also becomes a natural positional relationship. As a result, the right speaker 4R is located on the right side, and the left speaker 4L is located on the left side. therefore,
The right speaker 4R is located near the right ear of the awake person 5, and the left speaker 4L is located near the left ear.

(2) Generating circuit before raindrops Figure 8-(D) shows a raindrop sound generating circuit using PUT.

The eighth position shows a relaxation oscillation circuit using PUT. In the figure, a time constant circuit of a resistor R1 and a capacitor CI is connected to the anode side of PUTQI, and a resistive voltage divider circuit consisting of a series circuit of resistors R2 and R3 is connected to the gate side. When the switch SW is pressed, the DC voltage of the battery E is supplied to the above-mentioned time constant circuit and resistor voltage divider circuit,
Charging of capacitor C1 is started. Capacitor C
When the charging potential of capacitor C1 becomes equal to the gate voltage divided by the resistor voltage divider circuit, PUTQI is turned on, and the charge in capacitor C1 is discharged using PUTQl and resistor R3 as a discharge path. When the discharge current i becomes equal to or less than the holding current of PUTQl, PUTQI is turned off. Next, charging of the capacitor C1 is started again, and by repeating the above operation, a relaxation oscillation pulse is outputted to the cathode terminal of PUTQl. When this relaxation oscillation pulse is passed through an audio circuit, a "photo"-like sound before raindrops is generated. It is known that a proper drip rhythm promotes falling asleep, so if the raindrops called ``Hoto'' are played at an appropriate rhythm from the above speaker, combined with the action of the heating and cooling device, it can further promote falling asleep. become able to.

The raindrop sound generating circuit shown in the eighth position may actually disturb sleep because the sound of raindrops is continuous and the level is constant. FIGS. 8(B) to 8(D) show embodiments of the present invention, and show a raindrop sound generation circuit that gradually reduces or lengthens the volume or period before raindrops. Figure (B) shows a raindrop sound generation circuit that gradually lengthens the cycle. This circuit is called a constant volume raindrop sound generating circuit with a fade-out period. The difference in configuration from the circuit shown in the same device is that a first power supply circuit consisting of a resistor R5 and a large capacity capacitor C2 is connected in parallel to a CR time constant circuit consisting of a resistor R1 and a capacitor C1. be. Resistance R2,
The DC stable voltage of battery E is supplied to the resistor voltage divider circuit of R3. Batch IJE constitutes a second power supply circuit. In this raindrop sound generation circuit, the first step is to turn on the power switch SW.
is turned on and the capacitor C2 is fully charged.

When capacitor C2 is fully charged, power switch S is turned on.
Turn off W. CR consisting of resistor R1 and capacitor C1
The time constant circuit is charged based on the charging potential of capacitor C2, and PUTQl is turned on when the charging potential of capacitor CI becomes equal to the midpoint potential of the resistor voltage divider circuit consisting of resistors R2 and R3, that is, the gate potential of PUTQl. do.

By turning on PUTQI, the charge in the capacitor C1 is discharged. When the charge in the capacitor CI runs out, charging of the capacitor C1 from the capacitor C2 starts again. As such operations are repeated, the charging potential of the capacitor C2 gradually decreases, so that the charging time for the capacitor C1 becomes longer. Enter, P
The on period of UTQl becomes longer and finally PUTQ
I no longer turns on. As a result, the period before the raindrops are output from the speakers gradually becomes longer, and eventually there is no sound.

Figure 8 (C1 shows a raindrop sound generation circuit in which the period before the raindrop is constant and the volume before the raindrop gradually decreases. This circuit is called a constant period fade-out volume type raindrop sound generation circuit. The difference from the circuit shown in FIG. 8 CB+ is that the power supply to the resistor voltage divider circuit consisting of resistors R2 and R3 is connected to the first circuit consisting of resistor R5 and capacitor C2.
It is supplied from the power supply circuit of °. With this configuration, as the charging potential of capacitor C2 in the first power supply circuit decreases, the voltage supplied to the resistor voltage divider circuit also decreases, so even if the charging time to capacitor C1 becomes longer, Since the gate voltage of PUTQl is lowered, the period during which PUTQl is turned on is always constant. In other words, the period is constant. However, when PUTQl turns on, the charging potential of capacitor CI also gradually decreases (therefore, the level of the oscillation pulse becomes lower and the volume of the raindrop sound becomes smaller. Therefore, the raindrop sound heard from the speaker is Although the cycle is the same, it will gradually become smaller as time passes.

FIG. 8(D) shows a raindrop sound generating circuit in which the period becomes longer and the volume becomes smaller as time passes. This circuit is called a fade-out cycle fade-out volume type raindrop sound generating circuit. In this raindrop sound generation circuit, a first power supply circuit consisting of a resistor R5, a diode D1, and a capacitor C2 is connected in parallel to a CR time constant circuit connected to the anode side of PUTQl, and a resistor is further connected to the gate side of PUTQI. Capacitor C3 and diode D in voltage divider circuit
A third power supply circuit consisting of R2 and resistor R5 is connected in parallel. With this configuration, by appropriately changing the sizes of capacitors C2 and C3, the eighth
CB+, (The operations shown in C1 are performed simultaneously to fade out the cycle (gradually lengthen the cycle) and fade out the volume (gradually decrease the volume).

Among the above raindrop sound generation circuits, the circuit shown in FIG. 8 (Dl) that fades out the volume together with the cycle is the most preferable for inducing sleep.In this embodiment, this raindrop sound generation circuit with a fade-out period and a fade-out volume type is used. use.

FIG. 9 shows a raindrop sound generation circuit with a fade-out period and fade-out volume type used in the electronic heating and cooling pillow of this embodiment. Note that parts that are the same as or corresponding to those of the raindrop sound generating circuit shown in FIG. 8 are given the same reference numerals.

The power switch SW has a contact a and a contact S, which are connected to a positive terminal and a negative terminal of a battery E, respectively. A Zener diode ZD is connected to the output side of the resistor R5.
The voltage applied to the output side of the resistor R5 is stabilized to a Zener voltage. A timer circuit T is connected to the output side of the resistor R5. This timer circuit T includes a time constant circuit consisting of a transistor Q2 connected in series to a power supply line, a resistor R6, and a capacitor C4, a resistor R7 connected between the base of the transistor Q2 and the capacitor C4, and a switch SW. The diode D3 is configured to rapidly discharge the charge stored in the capacitor C4 when the capacitor C4 is turned off. When the power is turned on, charging of the capacitor C4 is started, but if the charging potential of the capacitor C4 is still low, a positive bias state is established between the base and emitter of the transistor Q2, and the transistor Q2 remains on. As charging of the capacitor C4 progresses and the charging potential reaches a level that blocks the base current of the transistor Q2, the transistor Q2 is turned off. When this transistor Q2 is turned off, the power supply to the raindrop sound generating section connected to the subsequent stage is cut off. That is, power can be supplied to the raindrop sound generating section only for a certain period of time from when the power switch SW is turned on.

The raindrop sound generating section basically has the same circuit configuration as shown in FIG. 8fD). Output side of resistor R5 and capacitors C2 and C3
The diode D4. is connected to the charging terminal of the diode D4. D5 is
When the switch SW is turned off, each capacitor C2
, C3 to rapidly discharge the charges. The other circuits are almost the same as those shown in FIG. 8 (DJ), so they operate in a fade-out period fade-out volume type mode. That is, as the period gradually becomes longer, the volume becomes smaller.

(3) Raindrop sound signal and stereo signal mixing circuit, audio circuit FIG. 1 shows a circuit connected to the cathode terminal of the PUTQ1. At the cathode terminal A of PUTQl, that is, the oscillation output terminal of the relaxation oscillation circuit, two diodes D6. D7
is connected.

In this embodiment, since the oscillation output polarity is positive, the diode D6. D7 is connected. As a result, the relaxation oscillation output, that is, the raindrop sound signal, is supplied to two circuits by diodes D6 and D7, and each circuit has a resistor R9 and a capacitor C5.
It is taken out as an output by resistor R10 and capacitor C6. The respective output signals of the raindrop stand divided into two circuits are supplied from terminals C and E to the mixing resistor circuit.

FIG. 2 shows this mixing resistance circuit and audio circuit. This audio circuit has a right audio circuit and a left audio circuit, and the right audio circuit includes a right signal mixing resistor circuit MIX(R) including a jack terminal J(R) into which a right audio signal is input.

Further, the left audio circuit includes a left side signal mixing resistor circuit MIX(L) including a jack terminal J(L) into which the left side stereo signal is input.

The right side signal mixing resistor circuit MIX(R) has a resistor R20.
It is composed of a known mixing resistance circuit including a resistor R22, and mixes the raindrop sound signal input from the terminal C and the right audio signal input from the jack terminal J (R). The variable resistor VRI is a resistor that varies the volume of sound. Furthermore, the left side signal mixing resistance circuit MIX (L) has the same configuration as the right side signal mixing resistance circuit MIX (R) described above, and the raindrop sound signal inputted to the terminal and the left side signal inputted to the jack terminal J (L). Mix with audio signal. Variable resistor V R
2 is a resistor that changes the volume. Right side signal mixing resistor circuit MIX (r output is connected to A via capacitor CIO
The signal is output to MP (R), where it is amplified and output to the right speaker 5P (R). Further, the output of the left signal mixing resistor circuit MIX (L) is output to AMP (L) via a capacitor C1l, where it is amplified and output to the left speaker SP (L).

With the above configuration, as shown in FIG. 1, diodes D6. Due to the intervention of D7,
For audio signals, the diode D6. D7 becomes reverse bias. Therefore, the left audio signal and the right audio signal do not interfere with each other via the raindrop sound generation circuit, and it is possible to prevent left and right crosstalk. That is, it is possible to mix the raindrop sound signal with each audio signal while preventing crosstalk between the left and right audio signals.

In addition, in order to stabilize the operation of PUTQI in the circuit shown in FIG. In place of PUTQl and diodes D6 and D7, a circuit with the same function can be constructed using transistors.

FIG. 10 shows an example using three transistors. In the figure, the connection state of transistor Q3 and transistor Q4 shows an equivalent circuit of PUT. Similarly, the connection state of transistor Q3 and transistor Q5 is also PU
This is the equivalent circuit of T. That is, in this circuit, a first PUT consists of transistor Q3 and transistor Q4, and a second PUT consists of transistor Q3 and transistor Q5.
This is the same as using the UT in parallel, and raindrop sound signals are generated at the respective output terminals C and H at the same time. In this circuit, transistors Q4, Q5 and diodes D6, . Since it has the same directionality as D7, crosstalk between the right audio signal and the left audio signal can be prevented. In this example, transistor Q4. The collector-emitter portion of Q5 corresponds to the diode of the present invention.

FIG. 11 shows a characteristic diagram of the above raindrop sound generating circuit. The same figure shows the periodic change of the raindrop platform with respect to the elapsed time.
The same figure (B) shows the change in the size of the raindrop platform with respect to the elapsed time. As mentioned above, this characteristic can be varied by appropriately adjusting the sizes of capacitors C2 and C3 in FIG. Furthermore, the size of the raindrop platform shown in the same figure (Bl) can change its characteristics as shown in the figure by varying the volumes VRI and VR2.

(4) Operation of raindrop sound generating circuit and audio circuit In FIG. 9, the power switch SW is normally located at the contact point.

When the power switch SW is turned on in this state (when it is located at the a contact point), power is supplied from the battery E to the timer T. When timer T is supplied with power from battery E, it starts charging capacitor C4. Capacitor C
When the charging potential of the battery E is low, the transistor Q2 is turned on, so that the voltage of the battery E is supplied to the raindrop sound generator connected after the timer T. As charging of the capacitor C4 progresses and the charging potential reaches a certain level, the transistor Q2 is turned off.

At this point, the voltage supply from battery E to the raindrop sound generating section is stopped. That is, the timer T supplies voltage to the raindrop sound generator for a certain period of time after the power is turned on.

The above-mentioned timer T is connected to the capacitors C2 and C3 of the raindrop sound generating section.
It is fully charged when it is on.

When the timer T is still on even after the charging potential reaches a certain amount, relaxation oscillation of -foot volume is performed at a certain period.

When timer T turns off, this capacitor C
Relaxation oscillation in fade-out mode starts with C2 as the first power supply and capacitor C3 as the second power supply. After the timer T turns off, the operation mode of the raindrop sound generator including this PUTQl is the fade-out period, fade-out volume type mode, as described above.
The period of the relaxation oscillation pulse output to the cathode terminal of PUTQI gradually becomes longer as time passes, and the height of the pulse is proportional to the integral value of the pulse, that is, the volume)
gradually becomes smaller, and finally the oscillation stops.

The relaxation oscillation pulse, ie, the raindrop sound signal, output from the raindrop sound generator is transmitted to the diode D6. It passes through D7 and is supplied to the right side signal mixing resistance circuit MIX(R) and the left side signal mixing resistance circuit MIX(L). At this time, if the signal from the stereo device is not supplied to the jack terminals J (R) and J (L), that is, if the audio output terminal of the stereo device is not inserted into each jack terminal, the raindrop sound signal is supplied as is to the AMP, where it is amplified to an appropriate volume and output to the speaker. For this reason, the "hot" raindrops are outputted from the left and right speakers so that the interval between them gradually becomes longer and the volume gradually decreases. Since the speakers are arranged at both ends of the heat dissipation fin Ilb as shown in FIG. 3, raindrops can easily reach the human ear and induce a reliable sleep.

On the other hand, the jack terminals J (R), J (L)
When a stereo signal is input to , the right side signal mixing resistance circuit MIX(R) and the left side signal mixing resistance circuit M! The respective stereo signals and raindrop sound signals are mixed at X(L), and the mixed signals are amplified by the AMP and output to the respective speakers. At this time,
If you want to hear only the stereo signal, turn off the power switch SW. Then, the charges in the capacitors C2 and C3 are rapidly discharged, and the operation of the raindrop sound generator immediately stops. In this case, diode D6. Because of the presence of D7, interference between the left and right stereo signals can be prevented even without a switch for switching between the raindrop sound signal and the stereo signal. The magnitude of the stereo signal and raindrop sound signal is determined by the variable resistor VRI,
It can be adjusted by VR2. By appropriately setting this variable resistor, a moderate volume can be maintained. In addition, in this embodiment, as shown in FIG. 6, since the back surface of the speaker 12b is covered with a sealing material 12c made of urethane foam and the stake body 10a, a large puffy effect can be produced, and the sound quality with extended bass. becomes. Further, since the aluminum heat dissipation fin llb faces the front surface of the speaker 12b, the heat dissipation fin reflects and diffuses the mid-to-high pitch sound, improving the sound quality of the mid-to-high range sounds as well as the low range. For this reason, speaker 12
Even if a small device is used as b, high-quality sound can be obtained.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram of a circuit that divides a raindrop sound generation signal into two circuits in an electronic heating/cooling pillow using a raindrop mixing circuit according to an embodiment of the present invention, and Fig. 2 is a circuit diagram of an audio circuit including a mixing resistor circuit. The figure shows. Figure 3 is an exploded view of the electronic cooling/heating pillow, Figure 4 is its completed view, Figure 5 is a perspective view of the main parts of the electronic cooling/heating device, and (C) 6th to 6th use shows the usage status of the electronic cooling/heating pillow. Diagram to explain, 7th
The figure is a diagram showing a state in which the sound generator is attached. In addition, Fig. 8 (Dl) is a circuit diagram of a raindrop sound generation circuit using PUT.Furthermore, Fig. 9 is a circuit diagram of a raindrop sound generation circuit used in this embodiment, and Fig. 10 is a circuit diagram of a raindrop sound generation circuit using PUT. Another example of the generating circuit is shown in FIG. 11 (A1. (Bl is a diagram showing the characteristics of the above-mentioned raindrop sound generating circuit. - right speaker, 4L - left speaker, D6.D7 - diode.

Claims (1)

[Claims] (1) A circuit that mixes the oscillation output of a relaxation oscillation circuit configured with a PUT as a switching element into an arbitrary audio stereo signal, the oscillation output polarity of which is connected to the oscillation output terminal of the relaxation oscillation circuit as a forward polarity. A raindrop sound mixing circuit characterized in that two diodes are connected in a direction in which the signals are mixed, and a right signal mixing resistor circuit and a left signal mixing resistor circuit are respectively connected to the non-relaxation oscillator circuit side of each of the two diodes.