A Torch Made of LED

The circuit demonstrates a torch out of Light-Emitting Diode (LED).

Electronic Insect Repellent Circuit

The circuit was designed to repel any form of insect using complimentary metal-oxide semiconductor or known as CMOS.

Identifying Static Electricity

The design of the circuit established the usage of Field Effect Transistors (FET) , as a precise detector of static electricity. It detects the invisible fields of voltage encircling every item subjected to electricity by identifying the occurrence of negative ions.

Bicycle Dynamo Regulator and Source Controller

Here is a bicycle dynamo regulator and battery charger circuit which is suitable for 6V/3W generator systems and 6V NiCd/NiMH rechargeable batteries.

Audio Intercom by LM380 and BC109C

This one is a high quality audio intercom circuit that consists of two identical intercom units and each unit consists of four parts which are a power supply, a microphone preamplifier based on direct coupled BC109C transistors, an audio amplifier based on LM380 2.5W audio power amplifier IC and "Push to Talk" relay circuitry.

Telephone Record Control by 2N4360 FET, 2N2222 and 2N2102

You can connect your phone to any recorder device which has a mic and remote control input. This circuit automates the recording process when the phone is in use.