Telephone talks are meant to be private or kept in between two persons engaged in the conversation. But, sometimes it is also necessary to have a group talk. The project entitled Telephone amplifier circuit serves us right. It is very simple, yet inexpensive and useful which uses very common power amplifier LM386 and some more components. The circuit can be used to produce loud sound to discuss or start a conversation in a group through telephone. Working of the  Telephone Amplifier Circuit The signal emitted as output from telephone is…
Read MoreCategory: Basic Electronic Projects
Different electronic project for entry level which are easy to build and understand.
Disco Light Circuit
Blinking and shimmering of lights in disco keep everyone amazed, the entire design cost of which might seem high. A circuit is presented hereby is of disco light making use of low-cost CMOS chip CD4011B, which is a two-input quad NAND gate. Along with two particular gates; G1 and G2 as shown in the figure below, it works as an RC oscillator forming clock oscillator gates. Circuit Description of Disco Light Circuit Here the two input terminals of the CMOS chip are coupled together to form an inverter. And, again…
Read MoreTouch Switch-Cum-Heat Operated Switch
We are updating day by day with different projects. Now, here we are going to post a very simple project using a few active as well as passive components called dual switches. As its name, it can be used as a touch switch as well as heat operated switch. Thus, we are calling it Touch Switch Cum Heat Operated Switch Circuit Description Touch Switch Cum Heat Operated Switch The circuit of the touch switch cum heat operated switch is very simple and easily understandable. It comprises three general-purpose transistors. The…
Read MoreEarth Quake Alarm Circuit
Here is a simple project called earth quake alarm circuit. This circuit is divided into two sections. Geo mechanical detector (Earth quake sensor) Alarm circuit The earth quake alarm circuit is based on the principle that earth quake create slow and suddenly vibration. In order to detect this vibration geo mechanical detector is used. The construction of geo mechanical detector is shown in figure 2. Alarm Circuit | Earth Quake Alarm Circuit The alarm circuit is built around dual input, 4 NAND IC (CD4011) and a NPN transistor. Input of…
Read MoreArduino Based Lie Detector
We have previously posted the the project lie detector, now here is is also a lie detector  using arduino.  Here is a simple tutorial to build a simple lie detector which will give visual indication  through LED arrangement whether the person speaks lie or truth.  The project uses a arduino duemilanove or uno. So the project is based on arduino. But our final circuit will be standalone circuit without attached arduino programmer. Circuit Description: Wiring diagram is very simple, we simply connected three LED to 3 different digital pins as…
Read MoreLuggage Security System
Introduction to Luggage Security System Number of thefts and robbery has increased to a greater extent. Unemployment, poverty might have been the cause for this but still stealing others property is a serious crime. The only way to stop this is by alerting people themselves with proper security arrangements. Bus hijacking is what we heard commonly of, this is where the fear of crime lies. We have seen people stepping ahead for protection, they use chains, lock as security arrangements to secure their luggage. This might be a nice try,…
Read MorePest Repeller Circuit
No matter how far we try to escape from pest’s trap or we attempt to clean the surrounding around us, we get eventually bothered being followed everywhere from kitchen to every corners of our house. Different pest repeller circuits have been developed claiming to escort people through this problem. However, pest repeller circuits thus built are found to have low power output resulting poor effectiveness. And, this error gives no solution to our trouble. With this point as our main concern, we have presented a powerful pest repeller circuit that…
Read MoreRF Probe Circuit
In order to measure the RMS voltage between two specific points, employing heavy and bulky electronic devices sounds unusual. And, therefore a small handy instrument can be used to avoid such situations where the voltage (i.e. RMS) between two points at any distance; large or small can be determined. For this reason, the instrument RF probe circuit has been proven of great help for home users as well as for communication equipment service/design labs. Description and Working of RF Probe Circuit RF probe circuit is just an instrument to measure, in…
Read MoreAdd on Device For Telephone
This electronic project, Add on Device For Telephone has multiple applications when used with the telephone lines. Since it is added parallel on the telephone system, it is called add-on device. The circuit add on device for telephone supports three modes of operation: on-hook, off hook, and ringing modes. It also provides the audio-visual indication of these operations. Using the relay, add on device circuit can connect the telephone to a CID (caller identification device). It can also be used to indicate tapping or misuse of telephone lines with the…
Read MoreMetal Detector Circuit
Metal detector is a device which is used to detect metallic object like metal coins, iron ore, aluminum or silver and gold etc. Here, we teach you how to make a metal detector circuit with which you can hunt hidden treasure. This simple metal detector circuit can also be used to detect buried cable or concealed wiring. You can also checkout metal detector using arduino. Description of Metal Detector Circuit This metal detector circuit is designed using three NPN transistors, IF transformer, search coil and few passive component. The metal…
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