Traditional doorbells are wired doorbells, easy to use, greatly facilitating everyone's life. If in the mansion or often can not hear the doorbell homeowners, sometimes always can not receive guests in a timely manner, it is very embarrassing. Now introduces how to make a wireless remote control doorbell to facilitate the owner in the room around the use of the doorbell button installed in the door, visitors just press the button, placed in the living room, kitchen or bedroom to receive the host will ring "ding dong" sound or music, bright and pleasant, informing the guests to come, the distance of a few meters to dozens of meters, there are usually 15 to 20 meters away. The receiver is powered by two five batteries, 3V when the actual measurement of standby power consumption = 0.48mA, extending the life of the battery. In-kind such as the following three pictures, size: transmitter 7.8cmX4.6cmX1.6cm, receiver 8.8cmX6.1cmX2.4cm, the original packaging has been used with the keys on the 12V A23 batteries, the receiver box on the upper part of a switch for the music to choose from, the receiver box can be hung on the wall, but also can be placed vertically on the high place, so that the effect will be better, and also is not easy to be easily removed by the children down the toys.
The following infinite electronic production network (Jiang Jieping) on how to make this doorbell in detail.
Material preparation: the transmitter side of the components needed are CD4069, 9018, 10 micro inductors, a 32.768kHz crystal, 12VA23 battery, a normally open button, part of the resistive components. The receiver needs components CD4069, 9018 a and 9013 two, 32.768kHz crystal, 10 micro inductors a, 1X2 toggle switch a, 2 tone music piece a, small Loudspeaker a, a number of capacitive components.
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Principle (graphic numbering does not correspond to the readers proofreading) To make a good wireless remote control doorbell. First of all, we need to understand the principle of its operation to do, please see the attached figure. Transmitter by the modulation oscillator stage and high frequency oscillator stage consists of two levels. Modulation stage circuit by a cheap domestic CD4069 and 32.768KHz crystal to complete, CD4069 is 6 inverter. The so-called inverters, that is, the most inverters have two ends, the input is a high level when the output is turned low, the input is a low level when the output is a high level, the input and output levels are always the opposite. As shown in Figure 1 feet and 2 feet for the first inverter, this paper called inverter 1, after that called inverter 2, 3, ......, the total **** CD4069 has six.
Transmitter switch is pressed, the inverter 1 and 2 and related components to form an oscillator generator, generating 32.768KHz low-frequency signal. Process: Inverter 1 of the 1-pin start low, 2-pin is high, 4-pin is also high. 2-pin high level by R2 on the crystal X1 charging, charging current through the R2 - X1 - inverter 2 of the 4-pin to the negative terminal. The charging time is determined by X1, and the equivalent capacitance is 200 P. Due to the charging of X1, the voltage on X1 rises gradually, positive left and negative right, and when it rises to the flip-flop level of the inverter 1, the 2-pin turns to a low level from the original high level, and the 4-pin turns to a low level at the same time. X1 starts to discharge, and the discharging path is R2 - 2-pin-negative pole of the inverter 1. Discharge X1 on the potential to reduce to a certain extent when the 1 foot to a low level, the output is flipped to a high level, once again on the X1 charging, this has completed a charge and discharge process, that is, an oscillation cycle, 4 feet of the output of a low and high level change. After the oscillation has been continued, the inverter 2 of the 4 feet will always output a constantly changing level signal. The frequency of this signal is determined by the crystal, which is 32.768 kHz, and the process explained above is accomplished very quickly when the circuit actually works.
Inverters 1 and 2 are used to generate an oscillating signal, and inverters 3 to 6 are used in parallel to form an output control that provides 20-30mA of incoming current. The outputs of inverters 3~6 are connected to the emitter of the transmitter tube Q1 to amplitude modulate Q1 and emit electromagnetic waves outward.
Q1, L1, C3 and 6P capacitors form a high-frequency oscillator, the oscillation frequency is determined by the printed inductors L1 and JC3 and the collector junction capacitance of the triode. Generally 200-270MHz. Q1's emitter if connected directly to the negative pole can produce equal amplitude high-frequency wave, and then connected to the output of the inverter so that the output is subjected to 32.768KHz oscillating signal modulation, through the printed inductance emission signal. The key is emitted every time it is pressed.
Q3, L3, C4, C5 for the super-regenerative oscillation receiver, L3 for the winding coil, in the diameter of 5mm skeleton winding, with 0.51 enameled wire around 3 turns, the middle of the skeleton with a copper core adjustment. When the oscillation frequency of L3 is resonant at the same time as the transmitter, the super-regenerative signal of Q3 is controlled by the amplitude-modulation signal of the transmitter, and L4 is a choke coil to prevent the high-frequency signal from passing through. Super-regenerative oscillator circuit has a self-checking function, the modulating signal after checking the waveform generates a voltage drop on R4, and is sent to IC2 for amplification, shaping and re-amplification through R5, C9, which is accomplished by three inverters 13 and 12, 11 and 10, 1 and 2, and C11 filters filtering out the high-frequency clutter after checking the waveform, and the signal-to-noise ratio is maximized by using a useful signal after checking the waveform. Modulated signal amplified by the three-pole with the transmitter (low-frequency 32.768KHz) the same frequency, X2 in the circuit plays a role in selecting the frequency, the same frequency of the signal can be passed smoothly, eliminating many unwanted interference from a variety of external signals, the frequency of the selected signal into the Q2 amplification and shaping of the signal amplitude is also low, the last two levels of open-circuit inverting amplification output equal amplitude square wave signal. r11 current limiting, C12 R11 current limiting, C12 filtering, the other side of the wave for smooth filtering, and tens of milliseconds of delay, but also to eliminate the outside world of the interference of the trigger circuit of the sharp pulse, K is the music selector switch, the music signal is amplified by the Q4 to promote the speaker to send out a beautiful sound of the doorbell music.
Assembly After the principle is clear, the next thing is the actual production. Of course there will be some problems. If you just do it according to the picture, it will not be successful, debugging is also very important.
Put the ready components, but also a homemade printed circuit board, there are many ways to make circuit boards, homemade experiments on the selection of the circuit board is not high, this time will not introduce how to make a circuit board. You have to make sure that the quality of the components, to be superior to be good.
The IC1's and peripheral parts are soldered first, X1 and high-frequency parts are not soldered. Now debug the CD4069 to see if it is normal, replace the X1 with a non-polarized capacitor of about 1 microfarad, temporarily replacing the X1, and connect a red light-emitting diode in parallel between IC1's pin 6 and ground. Turn on the power supply, the indicator should be flashing, otherwise 4069 is bad. Weld this capacitor, back to the original X1 welded, remove the light-emitting diode, the rest can also be welded. Then turn on the power, test the machine current between 4.8-5.5mA, which is the most important indicator, related to this range of 0.5mA or more to check whether the other reasons. Secondly, measure the b, e, c voltage value of each pole, the circuit vibration b for 5.5V-5.8V, e for 5.8V-6V, c for 13V or so. b pole voltage should be lower than the e pole voltage of zero a few volts, indicating that the circuit has been normal. Collector voltage will exceed the value of the supply voltage, which is a characteristic of high-frequency circuits. After the entire transmitter circuit is installed, it is close to an open short-wave (not FM) radio next to the launch, can be clearly heard in the launch part of the radio interference effects, so the transmitter is close to the completion of the installation and adjustment work.
Receiver according to the first installed high-frequency receiving part Q3 and peripheral circuits R3, R4, R5, R6, C4, C5, C6, C7, C8, C9, L3, L4, etc., connected to a 3-volt power supply, measured b e c three electrode voltages, respectively, 0.7V-0.8V, 0.2V, 1.3V-1.5V, the above is the measured value, for reference. L3 is wound 3 times with 0.51 wire with a 5mm diameter skeleton, as explained earlier. If you do not have a suitable adjustable copper core, this coil is fixed, C4 replaced with 5-20P adjustable capacitor, is also good. In Q3 emitter series ammeter measured I = 0.35mA or so. This level of work point has been basically normal. Then loaded X2 and all the relevant resistors, capacitors, IC2 (music and Q4 is not loaded), at both ends of the C12 and connect a light-emitting diode, pay attention to the polarity do not connect the wrong way, with tweezers to short-circuit the X2, you can see the light-emitting diode light up a little bit, it shows that the receiver is normal in the latter part. Transmitter and receiver circuit welding ended in a paragraph. C12 two ends of the light-emitting diode is not welded down for the time being, but also to be used later.
Note: Before welding, if it is made of circuit boards, the circuit design should be checked more than error before welding. Each device, especially the integrated block must be all normal. The outer iron part of the soldering iron can not carry static electricity, it is best to ground safely, lest damage to the device, bringing trouble. No parts of the value according to the requirements of the diagram, do not differ too much. The above principle part of the operating voltage and current is measured with a digital 830 meter, different multimeter measured value will be different.
Debugging First of all, you have to prepare a small audio amplifier to complete. The audio input cable through any way not to destroy the plug, transferred to two wires out, one is the ground wire and the other is the signal line, so that it is easy to debug can be soldered to the circuit board. Prepare a soldering iron, the amplifier input ground line soldered to the negative terminal of the doorbell receiver board, another signal line string a 103 capacitor and then soldered to the receiver board IC2 4069 2 feet. Open the power supply of the amplifier and receiver board, adjust the volume knob of the amplifier, you can hear the speakers emit a lot of "noisy ......" noise, indicating that you make the doorbell receiver high-frequency connection part is good. You can carry out the next step of debugging.
How to check the transmitter has been described earlier in the normal launch state, as long as the parameters of the assembly and the transmitter can be normal launch with the receiver board to try to adjust. Hand-held transmitter (remote control), from the receiving board 10cm ~ 40cm can be, change the distance at any time to press the launch button, intermittently pressed, carefully listening to the amplifier speakers in the noise volume, while using a non-inductive screwdriver to mobilize the copper core of the L3 or change the adjustable capacitor C4, that is, to adjust the receiver's receiving resonance frequency, so that it is the same frequency of signals emitted by the transmitter. Adjustment should be careful, slower (adjust the copper core can be faster, while adjusting the capacitance should be absolutely slow), when adjusted to a certain position can make the noise in the speaker disappears or become very small, or even inaudible. Then grasp the transmitter hand away from the receiver board, 1 meter or a few meters, press the transmitter can make the noise smaller. At this point the frequency has been tuned to be close to the same as the transmitter. Put the transmitter at a distance of 3-5 meters away from the receiver board, ask others to press its keys, you will be fine-tuned, this time should be more slowly around the mobilization (mainly to adjust the capacitor to do so), until the speaker in the noise than other positions in the smallest so far, the receiver was declared to be good. The amplifier's two input lines welded down, press the launch button you can see the C12 ends of the red tube light up, and delayed for tens of milliseconds to go out. The above receiver debugging method for unlimited electronic production network of commonly used methods, can also be said to be the exclusive method! We can learn from it.
To adjust the doorbell transmitter receiver, you may think that the distance can not reach your requirements, only 8-15 meters away, you can then upgrade. Find a section of 0.3-0.6mm diameter enameled wire, one end of the L3 on a circle, the other end of the loop bent into a circle, as an external antenna to enhance signal reception. As long as the shell can be put into the receiving box does not need to be very regular, the receiving distance of the receiving board can be increased to 10-20 meters away, enough for home use. Attention: after adding this antenna, the frequency of the receiver has to be fine-tuned again according to the method described earlier, it is fine-tuned, because the addition of the antenna will make the received frequency change a little. Adjustment of the device to complete all adjustments, with red absolute nail polish to seal it, to ensure the stability and reliability of the frequency, and at the same time again you can remove that red light-emitting diode.
Receiving part of the tune, the music piece and Q4, sound 0.25W8 ohm speakers installed, a complete ideal wireless remote control doorbell is made. How, see here heart, right, on their own good doorbell have unspeakable joy it!
Development of new uses According to the previous statement, you do not connect to the music piece, but in the R11 after a dual-stable trigger circuit, and then with a relay or SCR, can be used as a practical remote control switch or remote control lamps, and the performance is not worse than the market with the code. Add the compiled code circuit, do a high-quality remote control car model can also be a waterfall. If you want to do it, do it quickly, please contact the infinite electronic production network with questions.
Selection of materials To do any circuit has its key, the key to this circuit in the crystal X1, X2 and frequency adjustment. And X1 and X2 depends on the purchase, adjust the frequency depends on the skill. X1 and X2 in the electronic shopping mall is not easy to purchase, you can go to the general small school entrance or dollar store to buy two ordinary electronic table, back to remove the crystal which is 32.768KHz, electronic table price of about 1-2 dollars a. If you really can not find, the transmitter will be replaced by X1 200P capacitor, and then 820K resistor string a small 500K adjustable resistor instead of the original R2. 1mH inductor string a 0.022 microfarad capacitor to replace the receiver X2. tuning the receiver in the tuning to the amplifier speaker noise at the minimum hours, the light tube at the ends of the C12 will not be bright, but also continue to adjust the change of the 500K potentiometer, and the joint emission Receive the guandan light on, and then measure the total resistance value of 820K resistor and adjustable resistor, with the same resistance value of the fixed resistor replaced. This method increases the difficulty of the maker and reduces the possibility of success. It is recommended to still use the crystal inside the two spreadsheets to do.
The L1 on the transmitter board also has certain requirements, otherwise the difference between the received frequency and the transmitter is also too large to receive the signal. It is done on the printed board of copper foil, specifications can be made into a rectangular or round, uranium foil width of 1.5mm, the shape of the length and width of 1.2cm X 2.7cm, or 2cm in diameter, the amount of internal frame. Because the frequency of the receiving end is adjustable, the L1 can be made as long as it is roughly close to the above specifications. This rectangular or round coil can not use enameled wire to do, otherwise even if the tuning is good later, it is easy to run frequency, the signal sent out can not be properly received.
To do a good job of the board are packed in a suitable plastic box, the transmitter board can be installed separately in the door, lead a button to the door. Can also use the original security door comes with a box, remove the original doorbell circuit, very beautiful. However, it is best to be installed in the wooden object of the high place, the distance will be farther away. Receiving can be placed on the top of the kitchen, the top of the closet, bedside table drawers and other places. Circuit power consumption is extremely low, if you increase the resistance of the collector of the receiving transistor power consumption will be even lower, but the sensitivity of the reception to reduce a little. You can assemble it flexibly according to your needs.
After you read this, are you ready to install a it, installed don't forget to leave a message on this site ah! Infinite electronic production network Jiang Jieping
Originally left a message on this site to figure you can download the picture to experiment for your life to fill a fun, but also can greatly enhance the ability to do it, but also to make a practical doorbell, the receiver in the bedroom or where you want to place, so that you can always understand the situation of the guests when you go to bed to rest. Choose your favorite music, no music, do it yourself to make an audio oscillator, can produce a single tone. The above printed board charts and the difference between the real thing, users can buy doorbells on this site for learning and research.
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