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Two-tone doorbell circuit
Use the 48V (60V) DC feedback electric current which is provided by the phone feedback line as the working energy of the electronic doorbell is very economical and practical. Now I introduce one kind of two-tone doorbell circuit with out battery. The circuit is as shown, circuit in this figure is the variant of conventional telephone ringing...
electronic doorbell using UM3481
The heart of this circuit is the UM3481 IC which can be powered by a 1. 5 volts battery and can be used for electronic doorbell, toys, melody clock, music box, etc. The UM3481 IC is designed to play the melody according to the previously programmed information and is capable of generating 16 songs with 3 instrument effects : piano, organ and ma
2 Tone Door Bell
2 Tone Door Bell here published is verified project produce ding-dong sound circuit diagram of 2-tone door bell with description.various door bell and alarm project .
You cannot beat the Chinese. The project described in this article is a ready-made item from a $2. 00 shop! And it is made in China! It is a wireless doorbell with a cost of about $10. 00. It is so cheap, you could not build it from components for $10. 00! So, we have to change our attitude to building projects and use items such as this to...
Crank Doorbell Circuit Schematic
An interesting hobby circuit of a crank door bell! The circuit is built around a timer 555 and a musical piezo-buzzer. The circuit works off 9 volt battery supply. One 9volt PP3/6F22 compact battery is enough for powering the whole gadget. Timer IC (NE555) is wired in monostable mode to produce a time out o some seconds. The output of t
Sometimes you have to do it the hard way, even if doing it the easy way is an option. That is the case here. The intention is to add a second doorbell in parallel with the existing bell. This does not, in principle, require any electronic components. You would simply connect the second bell to the first one. But if the existing bell transformer is
a doorbell for the deaf
Politely welcoming electronic doorbell
The politely welcoming electronic doorbell circuit is composed of the trigger control circuit, audio amplifier output circuit, music circuit, voice delay control circuit, and it is shown in Figure 3-122. Trigger control circuit is composed of the doorbell button S, magnetic switches SA, transistors V4, V5, resistors R3, R4, R6, diodes VD2, VD3,...
Two-tone electronic doorbell 1
The two-tone electronic doorbell circuit is composed of the input trigger circuit and audio output circuit, ans it is shown in Figure 3-107. The input trigger circuit is composed of the doorbell button S, transistor V1, resistors Rl-R3, capacitor Cl and dual D flip-flop integrated circuit ICl (Al, A2). Audio output circuit consists of the audio...
Wireless two-tone electronic doorbell circuit diagram
Transmitter: Pressing the SB will make the transmitter circuit work. D1, D2 and R2, R3, C4 constitute a low-frequency oscillator to control the audio oscillator composed of the D3, D4 and D5, D6, then it works alternately. The generated audio signal is added to modulation side of Rf signal oscillator by C7. Then high-frequency oscillator signal...
birdie doorbell circuit
This is a design circuit for a doorbell. This circuit can produces a sound like bird sound. This circuit controlled by transistor NPN. This is the figure of the circuit. The operation of the circuit is beginning when P1 is of experimental value. Start with 220 Ohms or so and modify to suit your needs. The transistor is a general purpose kind and i
Instructions for wiring and installing a Doorbell in your home..
Three Flashing LED Doorbells For The Hearing Impaired
When the push switch is operated - the buzzer will sound and the LEDs will begin to flash. For the hearing members of the household - the buzzer acts as a regular doorbell. It also re-assures the visitor that the doorbell is working. When the push switch is released the buzzer will stop - but the LEDs will continue to flash. The length of time the
Sometimes you have to do it the hard way, even if doing it the easy way is an option. That is the case here. The intention is to add a second doorbell in..
If you re expecting an important visitor but you just have to step out for a moment, an electronic doorbell memory can come in handy so you can see whethe..
using doorbell circuit control things radio control
Modify it to click and latch a relay when i press the button from any ware in the house. Also if it is somehow possible unlatch the relay when pressed again. Im sure you know what i mean. I was looking at it, all i think i have to do is create some sort of maybe, flip flip circuit (if i understand what they actually are correctly) so itwill take...
Door Bell Circuits
CUSTOMIZE YOUR DOORBELL
It is very important to know about the pins of the IC in order to build the circuit. 1GND - Ground, low level (0 V) 2 TRIG -. One day i went to my friends house and noticed that his doorbell gave a sound similar to a cuckkoo bird, whereas mine was a simple one. Then i thought that why not make a doorbell that would shake everyone like that of a...
Remote Doorbell Controller
I usually can`t hear the doorbell when I`m in the basement. This project describes how to add an inexpensive remote doorbell to your existing household doorbell. My doorbell runs off of a 24VAC transformer that is live all the time. Someone presses the button and the bell sounds. To implement this project, it is necessary to tap 3 conductors...
Password electronic doorbell 1
The password electronic doorbell circuit is composed of the electronic password circuit and music occurred circuit, and it is shown in Figure 3-118. Electronic password circuit consists of integrated circuits lCl and keys Sl-S6, diodes VDl-VD5. lCl is the electronic password IC, its pin 1-3 and pin 6 are the effective transmission input ends,...
Password electronic doorbell 2
The password electronic doorbell circuit is composed of the trigger circuit and music generating circuit, and it is shown in Figure 3-119. Trigger circuit is composed of the buttons S1-S9, four NAND gate Schmitt trigger integrated circuit IC1 and the external RC components. Music generating circuit is composed of the integrated circuits lC2 and...
Two-tone electronic doorbell 2
The two-tone electronic doorbell circuit is composed of the trigger control circuit and doorbell generating circuit, and it is shown in Figure 3-108. Trigger control circuit consists of doorbell button S, resistors Rl-R3, electrical wear devices Cl-C3, diodes VDl-VD3, six NOT gate integrated circuit ICl (Dl-D6) and the electronic switch IC lC3...
Pictures Of Doorbell Circuit
Doorbell Warning Switch
This circuit will light a lamp at a remote location when the doorbell switch is pressed. This circuit should only be used with the solenoid type doorbells, the electronic type that play tunes will not work here. It is quite easy to miss the sound of a doorbell if you are watching TV, this circuit gets round the problem by providing a visual indic
Advanced Melody Doorbell
Advanced Melody doorbell is the very interesting project in the series of alarm Circuit diagram with description of melody doorbell using battery instead of AC mains .
Mark Harrington 3 in 1 Door Bell
Mark Harrington 3 in 1 Door Bell. The circuit comprises the power supply which is formed by TR1, Q3 , D13 , Q1 , D9..
electronic doorbell circuit
This is a design for a door alarm circuit, but in this design using electronic system. This circuit uses a synthesized sound chip from Holtek, the HT-2811. This circuit reproduces the sound of a "ding-dong" chiming doorbell. Additionally, the circuit includes a CMOS 4026 counter display driver IC to count your visitors. This is the figure of the c
You could really use any phone for this project, so don`t worry if you can`t get or don`t want the same model as mine. If you do get an antique bakelite phone, here are some basic steps for restoration. Clean your phone with a rag dampened in one of those environmentally friendly orange based cleaners. If the bakelite is heavily worn, cracked, or
This smart doorbell system is designed for use in industrial environments. It is microcontroller based and controls a horn and a flash light..
Remote Doorbell Warning Switchs
The hardest part for this circuit was the title. It is quite easy to miss the sound of a doorbell if you are watching TV, this circuit gets round the problem by providing a visual indication, i. e. a lamp. As an alternative, a LED could also be used. You could just parallel a lamp across the doorbell, but this would mean extra drain from the doorb
3 in one doorbell
The circuit comprises the power supply which is formed by TR1, Q3, D13, Q1, D9 This supplies both the 12 volt rails and the five volt rails for the micro which i..
555 Timer Circuits
RC Model Toy Circuits
H Bridge Circuits
Ultrasonic distance finder circuit
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is measured. There are three main categories of distance measurement methods in use: a) By...
Simple Metal detector circuit with CD4030
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to find something potentially valuable, hidden a few centimeters below the soil. So many...
Fully automatic watering circuit for flower pots
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This circuit comes as a solution to this problem. Depending on humidity of the pot at...
Simple deep searching metal detector circuit
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the circuit of this metal detector, it is possible to detect a metal coin in depth of 90 to...
Sub-Harmonic Bass Converter for Electric Guitars
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound, such as filtering or distortion. Instead, a frequency division system produces outputs...
Echo Depth Sounding Sonar for Boats
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the calibration of the rope. This arrangement still exists in some yachts. The big...
100W HiFi Audio Amplifier Circuit
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power supply must be symmetrical so that no electrolytic capacitors are needed at the outlet....
Plant-Pot Water Level Indicator Circuit
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower. The circuit of the device is shown in Figure 2. The water detection is made from the bottom...
Analogue Sound Preasure dB-Meter Circuit
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to have a good accuracy we will get the limits of 20Hz to 20KHz. A sound to be heard does...
DIY HV Variable Capacitor
DIY PMA Alternator Plans
Digital Signal Integrity