Radio Wave Alarm with MC14093BCF

Description:

This simple circuit is sure to have the police beating a path to your door - however, it has the added advantage of alerting you to their presence even before their footsteps fall on the doormat...

Sound Operated Switch with BC109

Description:

This sensitive sound operated switch can be used with a dynamic microphone insert as above, or be used with an electret (ECM) microphone. If an ECM is used then R1 (shown dotted) will need to be included. A suitable value would be between 2.2k and 10kohms...

High Current Power Supply with LM317 Regulator

Description:

This is an high current regulator that you can see above. There is an extra winding (or seperate transformer) which is used for powering the LM317 regulator. So the pass transistor operates closer to saturation and improves efficiency...

0V-12V / 700mA-2A Easy Build and Low Cost Power Supply

Description: 

This is circuit simple power supply adjustable voltage output 0-12V and Current output 0.7A - 2A . It is easy circuit and easy to build. low cost too. read detail in image circuit...