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Take any professionally made PCB and you will find that in most cases areas between traces are filled with copper areas. In fact background fills can give benefit but also be harmful to your all design. Dangerous prototypes have written a tutorial on how to make MCB background fills look professional and add additional features to schematic.

In most cases background fills are connected to GND in order to reduce resistance and electric noise. Keep in mind that filing grounds where ever it fits can also have negative effect – for instance ground planes near signal traces may add parasitic capacitance. In this case probably better use hatched fills or avoid them at all.

Sometimes it is useful to draw custom ground planes around power traces to make them more thicker in order to carry more current.

As electronic enthusiast you probably have pile of resistors, capacitors and other electronic components. Most of them are color coded and in order to use any of these you need to identify each of them. Usually resistor color band table works fine or multimeter. But how to speed up process a bit, free your hands and even eyes from looking at tables or multimeter. Anthony coded a simple application (EEspeak) which simply listens to you what type of element and colors are identified. Imagine sorting things out – sitting around with pole of resistors and reading each color values aloud.

Voice recognition seems to work great without any training. It can tell color coded resistor, capacitor and inductor value with its tolerance. Simple commands enable it to read values aloud and display on screen. Program is free so give it a try – at least it's fun.

Power down feature is very handy on battery operated devices. For instance most of multimeters already have this feature allowing them to self turn off when there is no activity for some time. Check out this simple solution which uses pair of FETs and resistor.

It was originally made for Atmega328 project because author didn't want to bother with AVR power down modes. Instead he used this simple circuit. It can be used to turn device on with switch this is where P-FET part plays role and turn off with N-FET. Turn Off signal wire comes from AVR pin market as 5. While device is powered N-FET has to be on with high gate signal. When N-FET gate signal goes low device turns itself off. This can be used on any device where possible to get such signal conditions. Or simply use in microcontroller circuit by adding some delay count after inactivity.