SEX TRONICA

  If you are a fan of electronics, which is an exciting world that slowly gaining ground in my interest, I would like to try to build this c...

Magnetic Gun

Picured in Figure 1 is a miniature magnetic gun. When optimally tuned, it will propel a small slug about 1.5 metres high, or 2.5 metres hor...

Scoring game circuit

Description. A simple scoring game circuit that can be used for all occasions when a dice is needed.The circuit is based on a NE555 time...

Digital code lock

Description. This is a simple but effective code lock circuit that has an automatic reset facility. The circuit is made around the dual fl...

Cell phone jammer

A beautiful mobile cell phone jammer schematic diagram for use only in GSM1900 with frequency from 1930 MHz to 1990 MHz. The GSM1900 mobile...

Cellphone Scanner

Here is a device to locate the mobile phone. It emits intermittent flashes and beeps to indicate the presence of an active mobile phone. The...

Ultrasonic pest repeller

There are many ultrasonic pest repellers available on the market but a major drawback is that their power output is low and their effective...

Combination Lock Circuit

Combination Lock circuit This circuit is very basic to build. To open a the lock which is connected to the K1 Load. you must press each mom...

Power Reminder Beeper Circuit

This hobby electronic circuit produces a short beep once each minute. It is powered directly off the 120vac power ...

Digital Message Recorder

The purpose of this digital electronics project is to record messages using a dedicated voice recorder integrated circuit. Recordings are st...

LASER based Door Alarm

This door alarm is based on the interruption of Laser beam. A low cost Laser pointer is used as the source of light beam. When somebody brea...

Electronic Stethoscope

An electronic stethoscope is used to listen to your heartbeat and you would normally use a listening tube or stethoscope. This electronic s...

Mobile phone sniffer – gsm telephone detector

This handy, pocket-size mobile transmission detector or sniffer can sense the presence of an activated mobile cellphone from a distance of ...

Light Dark Sensor With Relay Circuit Using LM741

Above is a schematic diagram of an LM741 light/dark sensor circuit (from the excellent 741 Op-Amp Tutorial by Tony van Roon). The ECG128/...