1.3W RF Amplifier

This diagram is a schematic diagram of RF amplifier circuit. The circuit will amplify the RF signal about 10 times, 100mW input power to 1.3W output power. It use a general NPN RF transistor 2SC1970. You may apply other transistors, for example 2N442. Circuit Diagram: Circuit Works: RF system and specially in RF amplifiers, this… Read More »

Automatic 9V Battery Charger

This is the scheme diagram of automatic 9V battery charger circuit, the parts list provided below the schematic image. The circuit was designed by Jan Hamer, translated by Tony Van Roon dan republished in this circuit diagram site. The circuit details are based on european standards: 120E, 150E, etc. The ‘E’ just stands for Ohms… Read More »

NiCAD Battery Charger with Current and Voltage Limiting

The following diagram is the schematic diagram of Ni-CAD battery charger circuit which featured with current and voltage limiting to keep the battery lifetime. The lamp L1 will be light brightly and the LED will be out when the battery is low and battery charging in progress, but the LED is very bright and the… Read More »

ACTOR : Active Tone Control

The following diagram is the schematic diagram of Active Tone Control circuit, or we often call this circuit as “ACTOR”. The circuit is quite simple, easy build and inexpensive, you can build this circuit with minimum / low cost. Active Tone Control or ACTOR is an active electronic audio circuit that serves to increase the… Read More »

4 Band Equalizer

The following scheme diagram is the four 4 band equalizer circuit. Equalizer device is generally used to improve the fidelity of sound, to emphasize certain instruments, to remove undesired noises, or to create completely new and different timbres. This circuit operated with 12VDC symmetrical / dual polarity power supply. Power supply circuit provided on above… Read More »