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Stabilized Regulated Power Supply Circuit

This circuit of power supply, is very simple and easy to built, it can be assembled on a general-purpose PCB, finding its materials is very easy and cost-small. The output voltage is stabilized and is regulated in the region from 0V until + 15V dc, with biggest provided current 1 A. The regulation becomes with the P1. The Q1 is classic power transistor and it needs to be placed on a cool rib (Heatsink), when it works continuously in the region of biggest current it gets hot. The type of transformer is standard in the market.... [read more]

Remote Doorbell Warning Switch

This circuit should only be used with the solenoid type chime doorbells, the electronic type that play tunes will not work here.... [read more]

Monostable Flip Flop

The monostable flip flop, sometimes called a 'one shot' is used to produce a single pulse each time it is triggered. It can be used to debounce a mechanical switch so that only one rising and one falling edge occurs for each switch closure, or to produce a delay for timing applications.... [read more]

Electronic Selector for 10 sources with Display-Relay Drive

This is a circuit for alternative sources selection. It combines mechanical selection using a rotating switch S1, the electronic drive of the relays RL 1-10 and also the optical indication of the selection by the Display DSP1.... [read more]

Low Voltage Alarm

This low voltage circuit can be used to monitor batteries and other volatile sources of current for problems. The circuit sounds an alarm and lights an LED, but can be interfaced to any number of other circuits for many different uses.... [read more]

Capacitive Sensor

The purpose of this circuit is to animate shop-windows by means of a capacitive sensor placed behind a post-card-like banner.... [read more]