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Wireless Lock Tone
When I got the car I was relieved that it didn`t "chirp" or blare the horn every time I locked or unlocked the doors. Let`s face it, there are times when we don`t want our comings and goings announced in such a tactless manner. Still, I found that in the daytime, when walking away from the car, or after forgetting until I`m some distance away, I c
555 timer bassed Electronic lock circuit with explanation
A very simple electronic key code lock circuit that require few external components can be constructed using this schematic diagram. This electronic key code lock circuit is based on a common 555 timer circuit and some other common components. This low cost key code circuit use six switches that needs to be pressed to open the lock, but only two
Arduino RFID Door Lock
The first step to building a RFID door lock with a basic Arduino is to bread board out a basic working arduino. Most Arduino pre-flashed ATMega 168 chips come with the default blink program pre installed. Connect a LED to digital output 13 and verify that everything is working. The hardware portion of this RFID reader would be too simple if we use
Door Lock Wiring
3-wire door locks can be either positive (diagram below), or negative. There is either a constant ground or positive wire that makes contact with either the lock or unlock wire when the switch is pushed. The idea here is to add relays that will make the alarm`s lock and unlock outputs to do the same thing the switch does. 3-wire door locks are use
electronic combination lock LS7220
The following diagram is a very easy and simple electronic combination lock based on IC LS7220. Component Part List: C1 = 1uF 25V C2 = 220uF 25V R1 = 2. 2K Ohm Q1 = 2N3904 / 2N2222 D1 = 1N4148 / 1N4001-1N4007 K1 = 12V SPDT Relay / Any appropriate relay with 12V coil U1 =. This is the circuit diagram electronic door lock security key system. It mea
Electronic Combination Lock
Electronic Combination Lock. This circuit is very basic to build. To open a the lock which is connected to the K1 Load you must press each momentary switch in the correct sequence. The.
Door lock Motor
The measured resistance of door lock motor was about 2 ohm. Therefore, supplying 5V, the current becomes 5v/2ohm= 2. 5A. Regarding that the peak output current of L293B is 2A, the current flowing inside the motor is slightly over 2A, but it does not occur any problem because the motor will be used just for several seconds. Voltage regulator (LM7805
Simple Code Lock
The above cycle is therefore repeated only when S7 at the Q1 output is pressed in time. When all keys have been pressed in time and in the correct order, Q7 goes 5 high for about 4 seconds to enable driving the unlock circuitry, e. g. a relay driver for an j automatic door opener. At the i heart of the circuit is the `Type 4022 octal counter. In th
Electronic Keypad Combination Lock
When wired to a ten-digit keypad, the circuit will recognize one 4 digit combination out of a possible 5040 codes. When the programmed four-digit combination is entered from the keypad, in proper sequence, LOCK turns on and Lock Status turns off. The lock combination is set by pins 3, 4, 5 and 6 on the LS7220. These correspond to the digits on...
PIC Microcontroller-Based Electronic Lock
Electronic Lock Project
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Light circuit diagram: Intelligent Electronic Lock
This intelligent electronic lock circuit is built using transistors only. To open this electronic lock, one has to press tactile switches S1 through S4 sequentially. For deception you may annotate these switches with different numbers on the control panel/keypad. For example, if you want to use ten switches on the keypad marked 0` through 9`, use
Electronic door code lock
Password Based Autoomatic Door Lock Using PIC16F877A
electronic combination lock circuit
a simple electronic combination lock using IC LS 7220. This circuit uses a relay for controlling any type of device when the combinations of four digits are pressed. Keypads are used as input here to enter the digits and the correct combination will activate the relay and the door or deice can be operated. The combinat
simple electronics code lock system
door lock schematic
Advanced power door lock management is a necessity now given today`s complex automotive systems. The need to reduce vehicle weight has prompted these more need a schematic for the drivers door lock mechanism for a 93 chevy g-20 The third wire changes, reading continuity to ground or (+) 12 V DC depending on the position of the door locks.
phase locked loop pll oscillator
This 860 MHz Phase Locked Loop (PLL) oscillator circuit is for 1200 MHz transverter`s local oscillator with 435MHz rigs. The oscillator circuit uses PLL synthesizer IC`s of Toshiba for PLL circuit. TC9122P is easy to use preset counter for determining request frequency value by patching. TC5081AP is phase comparator and TC5082P is binary counter f
combination lock in electronic
This is the circuit diagram of a combination lock electronic simple using CI LS7220. This circuit can be used to activate a relay to control (the & off) press any device when a preset combination of 4 digits. The circuit can be operated from 5V to 12V. Specify connection combination the appropriate parameters to pin 3, 4, 5 and 6 IC through the...
I-button electronic lock circuit
simple low cost digital code lock
In those circuits a set of switches (conforming to code) are pressed one by one within the specified time to open the lock. In some other circuits, custom-built ICs are used and positive and negative logic pulses are keyed in sequence as per the code by two switches to open the lock. A low-cost digital code lock circuit is presented in this...
build this versatile electronic combination lock part one
digital electronic lock
The digital lock shown below uses 4 common logic ICs to allow controlling a relay by entering a 4 digit number on a keypad. The first 4 outputs from the CD4017 decade counter (pins 3,2,4,7) are gated together with 4 digits from a keypad so that as the keys are depressed in the correct order, the counter will advance..
Digital code lock
This is a simple but effective code lock circuit that has an automatic reset facility. The circuit is made around the dual flip-flop IC CD4013. Two CD 4013 ICs are used here. Push button switches are used for entering the code number. One side of all the push button switches are connected to +12V DC. The remaining end of push buttons 2, 3, 6, 8...
One transistor code lock
This is of course the simplest electronic code lock circuit one can make. The circuit uses one transistor, a relay and few passive components. The simplicity does not have any influence on the performance and this circuit works really fine. The circuit is nothing but a simple transistor switch with a relay at its collector as load. Five switches (
Electronic Combination Lock Circuit using IC LS 7220
This is the circuit diagram of a simple electronic combination lock using IC LS 7220. This circuit can be used to activate a relay for controlling (on & off) any device when a preset combination of 4 digits are pressed. The circuit can be operated from 5V to 12V. To set the combination connect the appropriate switches to pin 3, 4, 5 and 6 of the...
WSH412 Hall Effect Sensor IC With Thermal Lock Protection And Auto Restart Function
The XC6119 series is a highly precise, low power consumption voltage detector, manufactured using CMOS and laser trimming technologies. The device includes the built-in delay circuit. A release delay time CAN be set freely by connecting an external delay capacitor to the Cd pin. The device using an ultra small package (USPN-4) is suited for high d
Simple Combination Lock
This simple combination lock accommodates codes from 1-9 digits long, with the only restriction being that the same digit cannot be used twice. The circui..
Key code lock switch circuit
This key code switch circuit is a type of electronic circuit that is created to replace conventional normal key switch. Without inserts a keys. But you can..
This is a simple but efficient Electronic lock. This lock can be used to protect any electronic systems from unauthorized usage. To get access the uses needs to know 8 digit pass-code or password. When the user enters correct 8 digit password followed by "Enter" button, it activates the relay allowing access to the system controlled by relay. If t
The RFID technology is fast penetrating the automotive market with the passive keyless lock application which will soon replace the remote control used to open or close the doors of the vehicle
digital code lock
The project called Digital Code Lock using AT89C2051 ². LCD is used for display and a keyboard is used to input the keys. This project source code is written in C. This a simple project with efficient hacking prevention from Brute Force etc. The basic user lock is of 5 Digits and Master Lock is of 10 digits so its not easy for an intruder to bre
Surveillance Bug 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