Category Electronics

How to use multiple solar panels?

Calculating watts Power[watt]=Voltage[volt] * Current[Ampere] if the panel is rated as 5v 200 mA then Power=1 watt Wiring multiple solar panels Parallel wiring This is required if your application need more power than rated. By connecting the positive terminal of…

How radio works?

How does radio works? Audio signals are transmitted by imposing lower audio frequencies on the high frequency carrier wave. In other words the audio signals are added to the carrier frequency. Its amplitude is modulated. At the receiving end, a…

Whats new in Raspberry Pi B+ board ?

The Raspberry Pi Model B+ is a credit-card sized computer board that’s up and running when a keyboard, mouse, display, PSU and SD card with installed OS are added. It’s a miniature ARM-based PC which can run many of the…

On-Off Switch using relay

Here’s how industrial equipment is started and stopped using push buttons(On-Off Switch). The circuit is called a “locked-out relay.” It uses an ordinary relay and the ON switch activates the relay to close the terminals. When the switch is released,…

Simple Battery Charger

Here is a very simple example of a low-cost battery charger for 12 v 7Ah lead-acid batteries. As shown in the figure, diodes 1N4001 (D1) and 1N4001 (D2) form a full-wave rectifier. The rectified voltage appears across SCR1 and the…

LED Driver using 7805 and LM317

LED Driver using 7805 The 7805 can be converted into a content-current device by connecting a resistor as shown below.   As the 12v rises from 0v, the 7805 starts to work and when the input voltage is 4v, the…