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Security Keypad - This Electronic Code Lock uses a 12-keys keypad is used to enter a password and open an electrick lock or any other device with a signal. Uses an 8-pin PIC 12F629. __ Designed by Jose Pino Security Keypad II - An improved version that can be used on security vaults, Doors with electric latches, Alarms, Safety devices and many other uses. it uses an HiTACHI LCD (16x1 or 8x1) and a matrix keypad. The HEX code is available for 16F84A and 16F628. __ Designed by Jose Pino
Security System Switcher - An audio signal can be used as a form of input to control any security system. For example, an automatic security camera can be configured to respond to a knock on__ Electronics Projects for You Seismic Sensor - My original "Deer Repellent/ Seismic Sensor" recommended using a speaker with a weight glued to the cone as a vibration sensor (see bottom of page) but it recently occurred to me that the speaker could supply the mass itself. By gluing __ Contact: Charles Wenzel of Wenzel Associates, Inc.
Sense multiple pushbuttons using only two wires - Sense multiple pushbuttons using only two wires figure 1Keyboards and numeric keypads often provide the user interface for electronic equipment, but many applications require only a few pushbuttons. For those applications, you can monitor multiple pushbuttons over a single pair of wires (Figure 1). __ Designed by Bernhard Linke, Maxim Integrated Products Inc, Dallas, TX
Sensitive Clap Switch Circuit - This is the circuit of a very sensitive clap switch. it switches ON/OFF a White LED or electrical appliances through claps. The circuit can sense the sound of claps from a distance of 1-2 meters. Condenser Mic picks up sound vibrations caused by the clap. These sound vibrations are given to the inverting input (pin2) __
Sensitive Temperature Switch - This temperature switch has a high sensitivity and is quite reliable. Here, in place of a single transistor, a Darlington pair has been used for switching. At normal room temperature germinum diode__ Electronics Projects for You
Service Request Beeper - A single press of a pushbutton switch turns on a beeper for one second but can’t be activated again for 60 seconds. . . . Hobby Circuit designed by Dave Johnson P.E.-September, 2005
Shock-Proof Remote Switch - Using this circuit, you can control any AC/DC appliance remotely through inexpensive, low-voltage cabling and a standard push switch. The circuit can easily support cable length up to 25 metres.__ Electronics Projects for You
Signal Detecting Auto Power on Unit - The switch detector unit is shown in Figure 1, and uses an LM358 dual OpAmp, and a handful of other parts. The relay switching device is a MOSFET, selected because of the almost infinite input resistance. The 2N7000 shown is recommended because it has a threshold voltage of less than 3V and is fairly cheap, but virtually any MOSFET will work just as well, even if the gate threshold is a little higher. An MTP3055 can also be used, as shown originally in this circuit. __ Designed by Rod Elliott ESP
Signal-Powered Switch Connects Devices - 05/10/12 EDN Design Ideas: Use a switch to selectively connect a terminal, personal computer, or any other originating device to one of four receivers. Design by James Dean, National Research Council, Ottawa, ON, Canada
Simple Touch-Sensitive Switch - This touch-sensitive switch is built around NAND gate IC CD4011 and transistor BC547. When someone touches plate 1 (which is connected between pin 1 of gate N1 and ground) , the RS flip-flop__ Electronics Projects for You
Simple Circuit keypad operated switch - I have modified the design to reduce the complexity of the circuit - and the number of components required. As a result - the code is somewhat less secure. However, there should be lots of situations where it will still be adequate. __ Designed by Ron J
Simple Circuit optical switch - The 555 is proved to be the most versatile and ubiquitous IC all over the world. This is a possible use: simple inverting schmitt trigger. When the phototransistor is stroken by IR light it conducts and the voltage between the 1Mohm resistor (arbitrary) and the phototrans drops from VCC to lower values. When the voltage drops lower than VCC/3 the 555 is triggered and goes high (from 0 TO VCC). __ Designed by Jonathan Filippi
Simple Circuit Voltage Switch for Car Sensors - This Simple Voltage Switch can be used anywhere you want a relay to switch when a voltage reaches a preset level. it has lots of applications in cars but can be used in any application where you have 12V DC available. Having switched the relay on, it will then switch if off as the voltage being monitored drops below the preset level.__ SiliconChip
Simple Mosfet Switch - Constructing a MOSFET switch is one of the basic level electronics projects and could be useful for beginners to get a hang of the various FET transistors. The aim of this project is to make control a heavy duty DC load by constructing a simple switch. MOSFET transistors are capable of handling a large voltage__
Simple Relay Circuit - The following schematic illustrates the Simple Relay Circuit Diagram. When the switch
is closed in a relay circuit, current flows in the coil, causing a strong magnetic field around the coil. The soft iron bar in the lamp circuit is attracted toward the right end of the electromagnet and makes contact with the conductor__
Simple Relay Step-Up Circuits - Have you ever needed to power a 12-volt relay in a circuit but only had 6 or 9 volts available? This simple circuit will solve that problem. it allows 12-volt relays to be operated from 6 or 9 volts, or 24-volt relays from 12 volts. While most normal relays require the manufacturer-specified coil voltage to__
Simple Under-Voltage Cut-Out - Sensitive low-current relay coils often operate at much lower voltages than their typical ratings. This can be undesirable in some applications, where low supply voltages can result in erratic system behaviour. in some instances, this problem could be overcome simply by inserting an appropriate value zener diode in series with the relay coil. This reduces__
Single Control Switch for Fan & AC - Here is an electronic switch that can be used to switch on both the air-conditioner as well as fan of your room, one by one. The circuit consists of power supply and__ Electronics Projects for You
Single Output 120VAC 200 Watt Touch Switch - This simple circuit uses a single IC to form a nice touch switch circuit. A single transistor forms the remote active switch sensor. Multiple switches can be wired in parallel. The switch circuit can be located about 500 feet from the control circuit. . . . Hobby Circuit designed by David Johnson P.E.-February, 2010
Single processor pin controls on/off function - 29-Apr-04 EDN Design Ideas: A recent Design ideas prompted me to offer the simpler solution that I used in a recent project (Reference 1]. We needed a momentary power switch with processor supervision. This supervision would allow the processor to delay a power-down request from a press of the power switch until all routines exited properly Design by Michael Sirkis, Radio Systems, Logan Township, NJ
Single switch controls digital potentiometer - 02/27/02 EDN Design Ideas: The control of electronic potentiometers in most today's applications comes from controller-generated signals. However, a significant number of applications exist that require adjustments using manual, front-panel controls. The circuit in Figure 1 uses one IC , one switch, and 10 discrete components Design by Chuck Wojslaw and Gary M Craig, Catalyst Semiconductor, Sunnyvale, CA
Single switch selects one of three signals - 2-Mar-06 EDN Design Ideas: Total cost is less than $1 - Low-cost, easy-to-use design allows monitoring of peripherals, sensors. Design by Felix Matro, JL Audio Corp, Phoenix, AZ
Single switch serves dual duty in small, microprocessor-based system - 03/30/06 EDN Design Ideas: Low-cost, easy-to-use design allows monitoring of peripherals, sensors Design by Steve Hageman, Windsor, CA
Single-IC-based electronic replaces mechanical switch - 03/15/07 EDN Design Ideas: Flip-flops debounce pushbutton switch - sample and inexpensive electronic circuit uses a low-cost pushbutton switch to toggle the electrical power on and off. The circuit replaces a more costly and bulky push-push mechanical swit Design by Santosh Bhandarkar, Bangalore, India
Single-wire keypad interface frees microcontroller-I/O pins - 31-Mar-05 EDN Design Ideas: Using this interface topology, you can reduce the number of keypad interface wires to just one and thus save critical microcontroller i/O ports Design by Israel Schleicher, Prescott Valley, AZ
Sink to Source Universal DC Converter - As illustrated below, many control systems use an open collector transistor to turn something on. Perhaps it is a LED light, a relay or a small motor. However there are other systems which require a common ground connection instead of a common V+ supply connection . . . Circuit by Dave Johnson P.E.-March, 2011
Six-way Switch - The 40106 is a versatile CMOS
IC containing six Schmitt trigger inverters. it can be used to implement a set of alternating-action switches with hardware contact bounce suppressionmust register on this site __ Designed by Published in Elecktor July/Aug, 2010
Slave Switcher - There are many situations where two or more pieces of equipment are used together and to avoid having to switch each item on separately or risk the possibility of leaving one of them on when switching the rest off, a slave switch is often used. __
Sleep Switch Cum Wake Up Timer - Here is a sleep-switch circuit that can be easily converted into a wake-up timer. A dual-mode time setting makes the system versatile. The circuit is low-cost and can function as a__ Electronics Projects for You
Sleeping Aid - Based on electromagnetic-field radiation; Place it under the pillow - Built-in timer __ Contact Flavio Dellepiane, fladello @ tin.it
Small Pushbutton Controls 10 Amps AC - The circuit below uses a pair of long lasting lithium coil cell batteries to power a latching relay circuit. With each activation of the small pushbutton, the relay is either latched closed or unlatched open. Since coin cells can’t provide the necessary peak current, a 500uF capacitor is used to store the needed energy. The circuit standby current is kept very low by using a stack of five 100uF ceramic capacitors instead of the usual electrolytic cap . . . Circuit by David Johnson P.E.-January, 2012
Smart Exhaust Fan Switch - Exhaust fans in washrooms can be connected to the lighting circuit so that these switch on and switch off with the electric light. But as washrooms are sometimes used only for__ Electronics Projects for You |
