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Web Hosting With Free Online Storage

If you already have a web hosting account you might want to ask how much space is available to you. Some hosting plans such as those at onlinebackup.org.uk offer additional storage for your personal files and some do not. Usually the cheaper the hosting account the lower the possibility that there will be enough storage for you. You will never know unless you ask you hosting company. If you find that there is not enough space for what you need you can purchase a separate account for your online back up or you can choose to go to a different hosting company with better plans. The choice as to what you will do is up to you but remember that there are some really great hosting companies out there that have affordable prices and will offer you free storage so you can back up your hard drive. Always start with your own hosting company first to see if you could perhaps add a little bit of space to your existing account. In some cases because you are already a customer it won’t cost much at all to upgrade. If you cannot make a deal then do some extra shopping around.

Test run of VFD display using Arduino

Among my electronics junk I found a VFD (Vacuum Fluorescent Display) display and wanted to make sure it still works and can be used in projects. It’s a 16T202DA1E display manufactured by Samsung.

16T202DA1E_hello_world

It can replace standard HD44780 based liquid crystal display out of the box. First of all it only requires 5V supply. Voltage step up circuit for lighting fluorescent display is already on board. Controller accepts same commands as any 2x16 LCD does. The pin-out of display is as follows:

OpenHardware RAM module for embedded projects

In more complex projects where audio or video are involved, microcontrollers usually run out of internal RAM. The only solution that stands out is adding external RAM. Depending on platform and solution used there are many ways of doing this. But usually goes SRAM modules, latch register(s) and probably some other additional circuits. If you only need to add more RAM without planning all this you can use RAM module like this one made by [Wardy].

external RAM

This is simple RAM module with 512Kbytes of static RAM. It only needs 13 pins for interfacing and can accept voltage levels 3.3V or 5V. PCB layout is designed so that pins are breadboard compatible – easy to play with any microcontroller or dev board like Arduino.

Zener – one diode for many uses

Zener diodes are specially designed diodes (heavily doped) that have low reverse voltage breakdown.

zener diode

Due to this characteristic zener diodes are connected backwards to normal operation. If zener is forward biased it acts as regular diode with forward voltage drop at 0.6V. Zener diod backward voltage breakdowns may range from 2.4V up to 100V. Truly speaking if you need like 1.2V then probably you need to connect two forward biased diodes in series for 0.6V+0.6V = 1.2V drop.

Diodes – how to choose one

Diodes are semiconductor devices commonly used for many purposes. In generally you can imagine diode to be a valve that passes current to one direction and stops it to flow back. First thing that comes in mind – this might be a good choice for reverse voltage protection. In fact they are. But...

diode symbol

In reality things are a bit different. First of all diodes aren't perfect devices. They have so called forward voltage drop which is about 0.7V for standard diodes. So if insert diode in to power supply, say 5V the after protection you will get 4.3V where part of voltage is lost in diode. If you wanna go this way – better choose Schottky diode instead which has a smaller forward voltage drop. Forward voltage drop occurs when diode is forward biased what means current flow from anode to cathode.

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by Dr. Radut