Scheme:
Taking into account all the shortcomings, the circuit was modified, as shown in the figure, and a new version of the acoustic relay was obtained. It was decided to abandon the control multivibrator, which creates interference leading to a loop, replace the powerful triac with a less powerful and more affordable triode thyristor, increase the relay sensitivity by introducing an additional amplifying stage, and introduce its adjustment, reduce the capacitance of the capacitor C5 and introduce an indication of the standby mode on LED.
Device:
The operation algorithm of the device remains the same - clap your hands, or another similar sound, and the lighting is turned on for two minutes, then the light is automatically turned off. The scheme of the sensor of acoustic vibrations on the operational amplifier K140UD6 is similar to the prototype previously described, and does not require explanations. Further, the signal through C5 goes to the sensitivity regulator at R5, and then, through C6, to an additional amplifier stage on the VT1 transistor. Then through C7 amplified signal enters the detector at VD3 and VD4. At the moment of the clap, some constant voltage appears at the output of this detector (at C8), which goes to the VT3 base and opens it. In this case, the capacitor C3 is discharged through the diode VD1 and the transistor VT3. A logical zero is set at the inputs of the element D1.1, which is kept during the charging time of the capacitor C3 through R3 (about 2 minutes). During this time, the output of D1.1 is kept at the level of a logical unit, which goes to the VT4 base and opens it. The current flowing through this transistor turns on the thyristor VS1, which turns on the lighting lamp. As soon as C3 is charged to a single level at the output of D1.1, a logical zero is established, and the transistor VT4 will close, the unlocking current will stop, and the thyristor VS1 will also close, thus turning off the lamp. The standby indication unit is made on the D1.2 element and the VT2 transistor. While the lamp is extinguished at the output of D1.1, a logical zero acts, it is inverted by the element D1.2 and a one from its output goes to the base of VT2, which opens and turns on the LED VD2. When the lamp is turned on at the output of D1.1 one and, therefore, at the output of D1.2 is zero, the transistor VT2 is closed and the LED is off.
Setting:
The sensitivity of the device is high, with the extremely high position of the slider of the resistor R5, the device is triggered by a low sound or hand clap at a distance of 6-8 meters. During installation, free input terminals D1 must be connected to a common wire. Do not allow the network wires to pass near the input circuits of OA A1. Microphone M1 - any dynamic.
Radioconstructor No. 4 2000 p. 38
With this device, you can automate the on / off switching of lighting or other household appliances: clap your hands, or click your fingers, or make any abrupt sound - the light will turn on; the next clap - the light turns off. The device allows you to adjust the sensitivity of the microphone, has a small size, is highly reliable, easy to manufacture, does not interfere with the power supply.
The load is connected to the open contacts of the relay on the printed circuit board, which, when clapped, close the load supply circuit.
| Parameter | Meaning |
| Upit. constant, V | +12...14 |
| Upit. No. constant, V | +12 |
| Ipotr. at Usup.nom., mA | ...1 |
| Ipotr. with active relay, mA | ...30 |
| Recommended power supply, not included |
PW1215B, ES18E12-P1J, GS15E-3P1J, GS25E12-P1J |
| Output load capacity | 6 A / ~ 220V |
| The size printed circuit board, mm | 83 x 38 |
| Recommended enclosure, not included | BOX-KA11 Housing plastic 90x65x30 |
| Operating temperature, ° С | 0...+55 |
| Operating relative humidity,% | ...55 |
| Production | Self assembly |
| Warranty period of operation | Absent |
| Weight, g | 300 |
A simple low-frequency amplifier is made on transistors VT1-VT3, which amplifies the signal from the MIC microphone to the required level. The trimmer VR1 can be used to adjust the gain. The well-known Schmitt trigger, widely used in radio engineering devices, is made on transistors VT4, VT5. A feature of the trigger is that it has two stable states that change with each arrival of a signal from the collector of the transistor VT3. Thus, with each pop, the trigger changes its state, and the relay periodically turns on and off the load. LED1 LED indicates relay actuation.
Structurally, the device is made on a one-sided printed circuit board made of foil-clad fiberglass with dimensions of 83x38 mm. For ease of installation of the device into the case, mounting holes with a diameter of 3 mm are provided along the edges of the board.
The work of the circuit. When you clap or click, the carbon powder in the microphone moves and changes its resistance. At the same time, at the junction point of the limiting resistor R1 and the microphone, an alternating component appears, which, through the separating capacitor C1, enters the base of the transistor T 1. Transistor T1 is both an AC and DC voltage amplifier. With the help of the resistor R2, the transistor T1 is in a slightly open state. The variable component supplied to the base is amplified by the transistor and, from the collector through the capacitor C2, is fed to the doubler rectifier assembled on the elements DD1, DD2, C3. The doubled constant voltage is accumulated on the capacitor C3, which is discharged along the circuit: minus the capacitor, resistor R1, base-emitter T1, plus the capacitor. At the same time, the transistor opens like an avalanche, relay P1 is triggered, its contacts are closed for the duration sound signal... When setting up the operation of the circuit, sometimes it turns out that its sensitivity is too high, it is triggered by cars passing along the street or from a wave of the hand near the microphone. It all depends on the type of relay used. The circuit can be roughened by connecting a variable resistor in series with the capacitor C1. In order to switch the load (light bulbs) using claps, it is necessary to supplement the circuit with a trigger. The circuit of such a trigger on a polarized relay is shown in Figure 2 - it has not been printed anywhere before.
When a sound signal (clap, click) is given, the contacts of the KR1 relay are temporarily closed. An alternating voltage of 220 V through the lamp L1, diode D1 is applied with a positive half-period to the end of the second winding of the RP-4 relay pin 8, the beginning of the winding pin 7, current limiter resistor R1, capacitor C1, closed contacts relay KR1, output 220V. The charging current of the capacitor C1 switches the relay armature to the left according to the scheme, the L1 light comes on, and the L2 light goes out, the D1 diode is blocked by the relay contacts, and the D2 diode is unlocked and ready for operation. When the next sound signal is received, the contacts of the relay P1 KP1 are closed. The voltage of 220 V through the lamp L2 and the diode D2 is applied by a plus to the beginning of the first winding, contact 5, from the output of the winding, contact 6 goes to the resistor R1 and recharges the capacitor C1. A polarized relay switches the armature to the right-hand contact. Diode D2 is blocked and D1 is ready for next cycle. Lamp L1 goes out, and lamp L2 comes on. Thus, when sound signals are received, alternate switching of the load occurs. In order for the trigger to perform the function of turning on and off only one light bulb, it is necessary to exclude one of the light bulbs from the circuit, and instead turn on a series circuit from a 0.33μF x 300 V capacitor and a 5–10 kOhm, 2 W resistor. When setting up the trigger, it is necessary to adjust the armature of the polarized relay so that it switches well and is securely fixed in the right or left position.
Correctly determine the beginning and end of the relay windings or change the polarity of one of the diodes. Of course, this design of an acoustic relay on a carbon microphone is more suitable for beginners, so in the next article it will be described on one microcircuit, and a piezoelectric element is used as a sensor.
Discuss the article SIMPLE ACOUSTIC RELAY
FM RADIO MICROPHONES Frequency modulation (FM) radio microphones are usually quite complex. So, in the FM radio microphone, the signal from the electrodynamic microphone is amplified by an operational amplifier, after which it is fed to the base of the transistor of the high-frequency generator. thereby realizing mixed amplitude-frequency modulation. Fig. 1 The design of the FM radio microphone can be greatly simplified by using small-sized condenser microphones connected directly to the oscillatory circuit of the high-frequency generator. Variants of possible circuits with such an inclusion are shown in Fig. 1-3. electrically isolated from stationary electrodes Acting as an element of the generator circuit, it thus performs frequency modulation. schemes in Fig. 1, units-tens of mW for schemes in fig. 2 and tens of hundreds (in the presence of radiators) mW for schemes in Fig. 3. The range, accordingly, varies from tens of meters to several kilometers - when using FM radio receivers with a sensitivity of at least 10 μV / m. The parameters of the inductors are similar to those given in. Literature 1. Ridkous V. FM radio microphone. - Radio amateur. -1991, N4, p. 22-23 M. SHUSTOV, Tomsk (RL 9/91) ...
For the "SOUND RELAY" circuit
Consumer electronics SOUND V. LAZOVIK, Makeevka. Descriptions of various options have been repeatedly published on the pages of popular publications. acoustic switches. Here is another circuit that I designed and produced more than nine years ago, and since then it has been working flawlessly in the corridor of my apartment. The circuit has time. After a short sound signal, the light in the hallway turns on and lights up for about four minutes, then automatically goes out. The scheme itself is embedded in the wall, the walls are covered with wallpaper. There are no switches in the corridor, the wallpaper is clean, which rarely happens when there is a switch, and children use it all the time. The scheme works as follows. Audible signal perceived electret microphone VM1 is fed to the DA1 microcircuit (microphone amplifier with a special frequency response) used in LEN-type radio stations. Drozdova transceiver circuits From the output of the microcircuit, the signal goes to the shaper rectangular pulses, assembled on two inverters of the DD1 microcircuit, and further to the base of the transistor VT1, which, opening, discharges the timing capacitor (SZ) of the Schmitt trigger. In this case, a logical "O" appears on the output element of the DD1.4 trigger, and a multivibrator, made on the DD2 microcircuit, is turned on. At the output of the multivibrator there is a pulse amplifier (VT2, VT3), from the output of which, through the separating capacitor C7, the signal is fed to the control electrode of the triac VS1. The triac opens and turns on the load. When the capacitor C3 is charged to the level of a logical "1", the Schmitt trigger goes into another stable state, a logical "1" appears at the output of DD1.4, the multivibrator turns off, the triac closes, and the electric lamp goes out. The exposure time is selected depending on the specific application of the circuit. At a nominal capacity SZ, u ...
For the circuit "Switching 12-volt electromagnetic relays from a voltage source"
The scheme proposed by R. Graham, allows switching 12-volt electromagnetic from a source with a voltage half as much. V original state T1 and T2 are closed, and C1 is charged to a voltage of 6 V along the R3-C1-D2 circuit. With the arrival of the control potential, T1 opens, connecting the positive plate C1 to the common wire and at the same time opening the transistor T2, which connects the upper terminal according to the scheme relay with a +6 V bus. Thus relay it turns out before the discharge of C1 under a voltage of 12 V and is triggered, and after the discharge of C1 under a voltage of 6 V, which, however; enough to keep him in this state ...
For the "Touch relay" circuit
For the diagram "Stabilized power supply 59 V 500 mA with relay protection"
Many radio amateurs make power supplies (PSU) with electronic system overload protection and short circuit... These are a little complicated and don't work consistently forever. In my opinion, it is much easier and better system PSU on electromagnetic relays. Below is a description of a power supply unit with such a protection system. The power supply unit has a power-on and overload indication on LEDs. This power supply unit can be used to power any radio devices with a supply voltage of 4.5-6 V, 9 V and a consumption current of up to 500 mA. It is very convenient to use for adjustment work, as it contains an overload and short circuit protection system, which guarantees the safety of work. ...
For the "Capacitive relay" circuit
Burglar alarms, switches for household appliances, control sensors on a production line are just a few of the applications for this capacitive relay. It can be used, for example, in the simplest home automation: I sat down in a chair - a floor lamp turned on, music began to play, a fan started up, etc. In a word, the scope of application will be prompted by the imagination, the creative thought of the radio amateurs themselves. relay depends on the tuning accuracy of the capacitor C1, as well as on the sensor design. The author has a maximum distance to which the relay reacts is 50 cm. Schematic diagram The capacitive one is shown in Fig. 1, the images of the mounting on the printed circuit board are shown in Fig. 2, and the design of the inductive coil with its placement and the sensor on the board is shown in Fig - 3. Coil L1 is wound on a multi-section polystyrene frame from the circuits of transistor radio receivers and contains 500 turns (250 + 250) with a branch from the middle of the wire PEL-0.12mm, Winding - in bulk. The sensor is installed perpendicular to the plane of the printed circuit board. K157ud2 power amplifier It is a piece of insulated mounting wire from 15 to 100 cm long, or a square made of the same wire, with sides from 15 cm to 1 m. The Cl capacitor is of the KPK-M type, the rest are of the K50-6 type. As selected RES-10, passport PC4.524.3l2, you can also use RES-10, passport RS4.524.303, or RES-55A, passport 0602. The VD1 diode can be excluded, since it is only needed for protection ...
For the "Capacitive relay" circuit
Consumer electronics relay Security alarm,. switches for household appliances, control sensors on a production line are just a few of the applications for this capacitive relay. It can be used, for example, in the simplest home automation: I sat down in a chair - a floor lamp turned on, music began to play, a fan started up, etc. In a word, the field of application of this will be prompted by the imagination, the creative thought of the radio amateurs themselves. Radius of action relay depends on the tuning accuracy of the capacitor C1, as well as on the sensor design. The author has the maximum distance to which the relay reacts is 50 cm. The schematic diagram of the capacitive one is shown in Fig. 1, the images of the mounting and the printed circuit board are shown in Fig. 2, and the design of the inductive coil with its placement and the sensor on the board is shown in Fig. 3. ... Circuits of the transceiver thrush The L1 coil is wound on a multi-section polystyrene frame from the circuits of transistor radio receivers and contains 500 turns (250 + 250) with a tap from the middle of the PEL-0.12mm wire. Winding - in bulk. The sensor is installed perpendicular to the plane of the printed circuit board. It is a piece of insulated installation wire from 15 to 100 cm long, or a square made of the same wire, with sides from 15 cm to 1 m. Condenser C1 is of the KPK-M type, the rest are of the K50-6 type. As relay selected RES-10, passport RS4.524.312, you can also use RES-10, sport RS4.524.303, or RES-55A, passport 0602. The VD1 diode can be excluded, since it is only needed for protection schemes from accidental reversal of the polarity of the power supply. Configurable capacitive ...
For the diagram "RELAY COOLING SYSTEM VAZ-2103 ... 2108"
For the scheme "ELECTROMECHANICAL PROTECTION IN CHARGERS"
Power supply ELECTROMECHANICAL PROTECTION IN CHARGERS D. ATAEV, Sterlitamak Chargers (ZU), as a rule, are equipped with an electronic short circuit protection system at the output. However, in amateur radio practice, there are still simple ZU, consisting of a step-down transformer and a rectifier. The necessary components for assembling electronic protection are not always available. In this case, you can apply a simple electromechanical protection using relay or circuit breakers repeated action (for example, automatic fuses or AVM in apartment electricity meters). The advantages of the proposed protection: simplicity and the absence of expensive semiconductor devices. Its disadvantage is its high inertia. The speed of the relay protection is approximately 0.1 s, using AVM-1 ... 3 s. When the battery (or rechargeable battery) is connected to the output of the device, relay K1 works and with its contacts K1.1 connects the charger (see K157ud2 power amplifier circuit). In the event of a short circuit, the output voltage will drop sharply, the winding relay will be de-energized, which will open the contacts and disconnect the battery from the charger. Re-inclusion after elimination of the malfunction is carried out with the SB1 button. Capacitor C1, charged to the output voltage of the rectifier, is connected to the relay coil. Resistor R1 limits the current pulse in case of erroneous switching on, when the short circuit at the output is not eliminated. Resistor R2 limits the short-circuit current of the rectifier diodes. It may not be included in the circuit if the diodes are designed for impulse currents of this value. Otherwise, resistor R2 is required. However, it should be remembered that the output voltage of the charger should in this case be greater for the role of the voltage drop across the resistor R2 at the rated charging current. AVM protects against overcurrent, that the relay ...
Sound relay and circuits for turning on the lighting with a call to mobile phone. (10+)
Automatic lighting control - Mobile control. Sound control
Sometimes it is useful to be able to turn on the lights by calling your mobile phone. For example, in order to reach the house at night, I need to turn on the floodlight that illuminates the road. The switch, of course, is at home.
I immediately decided that I would not open and re-solder my mobile phone inside. At first, it is illegal. Independent modification of devices that are subject to mandatory certification by law is not allowed. Secondly, there is no need for such a soldering.
As with previous devices, I chose the transformerless power supply option. This immediately necessitated galvanic isolation from the telephone. For safety reasons, the mobile phone should not be directly connected to the lighting network. I settled on three variants of the scheme: acoustic, optical and transformer decoupling. All three schemes respond to a call coming to a mobile phone. Since the connection is not established, the money is not debited, so the function is completely free if you select a tariff without a monthly fee for the phone in the control system. After the call, the lighting is turned on for a fixed time. After which it goes out, but you can turn it on by calling again.
Sound relay
The first option is to use sound relay that reacts to the sound of the phone ringing. The relay uses a computer microphone. It attaches to the phone in close proximity to the speakerphone of the phone, which emits the ringing sound. Usually this speaker is located on the back side. A telephone with an installed microphone must be soundproofed so that extraneous sounds do not cause interference. You can put it in a foam or polyethylene foam cover. Any phone with a working ring is suitable for the device. The phone is best connected to charger, plug in the charger and leave it forever. Please use the original charger so that it can work safely for a long time.
The device is connected to the power section, described on the previous page, at the points marked with the letters A, B, C, instead of the circuit on the photo relay.
Transistors: VT2- KT503, VT3- KT502. Diode VD5- KD510 or another similar low-power diode. Capacitors C4- 0.1 μF, C5- 2 μF.
Resistors: R10- 50 Ohm. This resistor must be selected in order to provide the desired sensitivity, so that the relay reliably triggers when a call is made, does not react to extraneous sounds. R11- 3 kOhm. R12- 50 Ohm. R13- 300 Ohm. R14- 50 Ohm.
All other details are as in the previous diagram.
T- a microphone from a computer. A microphone with a standard connector is connected as follows: the body - to the common wire, the pin - to the capacitor C4. If there is also a middle contact in the connector, then we simply do not connect it.
The circuit works like this. When a sound signal occurs, current pulses are fed to the base of the transistor VT2, since the base-emitter junction has one-sided conductivity so that the capacitor cannot discharge, the junction is shunted by a diode. Resistor R12 limits the current. The current pulses charge the capacitor C5 and open the transistor VT3. Capacitor C1 is charged through it. The light turns on. When the sound disappears, capacitor C1 is discharged until the lighting is turned off.
