This is a low current flasher consumes only a few Micro amperes current and lights a high bright LED day and night for more than one year. This can be used in switch boards, key stand etc to locate them easily. Unlike other LED flashers, it uses the current from the capacitor to light the LED. With a 9 volt battery, the LED flashes more than one year.

Here is a great collection of touch switch circuits. A touch switch is an electronic device that enables us to control a circuit by simply touching a sensor.

Industrial grade clear glass sensor modules are widely available but not within the reach of an average electronics hobbyist. The simple clear glass sensor circuit can be used for experiment/hobby purposes. The concept is very simple and is based on a home-made sensor unit comprising one high efficiency ultra bright red LED (D1) and a standard phototransistor 2N5777 (T1). The circuits works off a well regulated 5Volt dc supply.

Minuscule circuit of the electronic heater controller presented here is built around the renowned 3-Pin Integrated Temperature Sensor LM35 (IC1) from NSC. Besides, a popular BiMos Op-amp CA3140 (IC2) is used to sense the status of the temperature sensor IC1, which also controls a solid-state switch formed by a high power Triac BT136(T1). Resistive type electric heater at the output of T1 turns to ON and to OFF states as instructed by the control circuit. This gadget can be used as an efficient and safe heater in living rooms, incubators, heavy electric/electronic instrument etc.