Computerhilfen tech-tips

To change the volume of the Raspberry Pi and turn the computer up or down, you don't need a mouse or screen: This can also be done over the network via SSH. To do this, connect to the Raspberry (tip: Connect via SSH and activate SSH). Then you can activate the volume control with the following command:alsamixerThis starts the setting program shown in the picture above. Use the arrow keys (up and down) to change the volume: this is also shown gr... Read more...

The new Raspberry Pi 4 seems to have problems with the WiFi, if a screen with a high resolution is connected via HDMI: The small computer even has two Micro-HDMI outputs in version 4, which can deliver a 4k image. If the Raspberry Pi is to be used as a media player on a high-definition TV, however, it is better to connect it via LAN cable: With the Pi 4 this is now also possible with Gigabit.At higher HDMI resolutions, the video signal should inter... Read more...

The Raspberry Pi usually comes with a standard password for logging in. However, this should be changed quickly as it is a security risk: Anyone else can log in with the same password. Since mid-2019 Raspbian does not allow short passwords anymore: They must contain at least six letters.If you still want a shorter password (or no password at all), you can use a trick to set it up: To do this, you don't change it directly your your own user, usually... Read more...

After the first setup of the Raspberry's microSD card you can start the small computer: Once it has loaded all services, you need a password to log in: The Raspberry Pi default password for the login under Raspbian is always the same: No matter which Raspberry Pi and which Raspbian version you use, you can always log in with the same password. Therefore you should change the default password quickly: Otherwise other users will also have easy access to ... Read more...

In Google's search engine and the Google services are hidden numerous "eastereggs": These small jokes or even whole games can usually only be found by chance. Google shows one of the hidden eastereggs when you search for "<marquee>". This is the HTML command for a scrolling text. The Marquee command was introduced by Microsoft's Internet Explorer and are now also supported by the Firefox and Chrome browsers: However, the Firefox developers have c... Read more...

(Please click here for the german version)If the Raspberry Pi responds with the error message "Repository 'https://raspbian.raspberrypi.org/raspbian buster InRelease' changed its 'Suite' value from 'testing' to 'stable'", this simple trick will help: Since Raspbian Buster is now officially available as a "stable" version, you have to confirm this once: Then you can install new software again with "apt-get" without any problems.Before installing,... Read more...

A Google update for the Chrome browser is supposed to stop the Mac from working when Apple's System Integration Protection (SIP) is turned off: Then the Chrome Update deletes the symlink "/var", which is important for the operating system, reports Mr. Macintosh. This folder is needed for Linux and Mac systems and should point to "private/var" on a Mac: Without it the Mac won't start anymore.Affected by this problem are macOS 10.9 and 10.10: Apple's... Read more...

With the desktop version of Raspbian, but also with Debian or Ubuntu often come screen savers. They only make limited sense because they consume a lot of unnecessary resources on the small Raspberry Pi: Here it helps more to turn off the screen when it's not needed.If you want to remove the automatically installed screensavers, this short command will help you in a Linux console:sudo apt-get remove xscreensaverWith "sudo" you'll get root rights... Read more...

With the CSS property "box-shadow" you can easily add shadows to an HTML element: All you need, besides the color, is the size and both the vertical and horizontal position. So you can position the shadow only downwards, without a shift to the right or left!The code for a gray shadow with only a slight offset looks like this:box-shadow:1px 1px 5px #333333;The first value stands for a horizontal offset to the right or left, the second value for ... Read more...

The Samsung SyncMaster monitors are actually easy to assemble and disassemble: Only the foot of the monitor can be a bit stubborn. Unfortunately you also have to remove it to pack the monitor back into the Samsung box: Otherwise the monitor stand would stand out too far to close the carton.The round plate at the bottom of the stand can be removed easily: Usually there is a screw under the base that is easy to loosen. The foot is then attached to th... Read more...