How do I make an electronic device

Tip 149:
Electronics on diving station - electro-balneology

At first, the LJ editor thought of an April Fool's joke. But that's not the tip below, because it actually works.

In the laboratory, as in normal everyday life, you come across cell phones, PDAs, navigation devices, netbooks or computers at every turn. Like all electronic devices, they have an aversion to moisture. Nevertheless, it happens again and again that they come into more or less extensive contact with coffee, water, sweat, buffer solutions, chamomile tea with honey or disdainful cleaning water, which usually leads to a total failure. Good for those who then have access to a well-equipped laboratory and an IT or electronics workshop.

It is advisable to switch off a device that has been damaged by water immediately, otherwise short circuits can occur. In order to determine whether the good piece still works, it should be dried as much as possible before a test (possibly leave it to stand for one to two days at room temperature). If the device does not survive the short function test, we recommend the following spa treatment to make it fit again.

First you open the device, dismantle it as much as possible and remove rechargeable batteries or batteries (sometimes you have to unsolder them). The same goes for hard drives. These components are inherently watertight and therefore do not require any further treatment. The remaining components, including touchscreens, are usually astonishingly robust and survive the subsequent procedure without complaint.

The parts are rinsed extensively in distilled! (not deionized) water or submerge them and bathe them for one to two hours. If available, a shaking table helps to gently swivel the components in the water bath. This first treatment step removes chamomile tea, honey, salts and surfactants. What remains is water and possibly also coffee fat. So there is a second rinse and dip in 80% ethanol, analogous to the first. The ethanol dissolves the fat residues and also absorbs some water and evaporates quickly.

The washed parts of the device are then dried. The coarsest moisture, which is usually in poorly accessible places, for example between the display layers, can be removed by centrifuging for five to ten minutes at 10 to 20 g. Then a desiccator of the appropriate size and a vacuum pump will do a good job. Since moisture can persist in the fine cracks and corners of electronic components, you dry overnight.

Alternatively or additionally, the parts can also be incubated in a drying cabinet at 37 to 42 ° C, but the vacuum has proven to be more efficient with us. Then you have to reassemble or solder the parts (digital photos that you took during the dismantling process can be helpful here).

We have a slightly modified tip for keyboards: remove the keys and put the rest in the dishwasher at home, which you can run with very little detergent. A large desiccator is required to dry the keyboard. Those who do not have this can use the ultracentrifuge for purposes other than those intended. The rotor chamber of the ultracentrifuge (without rotor) can be vacuum sealed and offers enough space for a complete keyboard. The misused centrifuge should, however, as far as possible not be set in rotation and run.

We have successfully tested this procedure on cell phones, PDAs, notebooks and keyboards. Incidentally, the risk that you run is very low, because if the bathing procedure goes wrong, the device is just as broken as it was before the action.

Peter Nielsen & ChristophGartmann
(Max Planck Institute for Immunobiology and Epigenetics, University of Freiburg)





Webmaster's Note:

The following pictures are not for the faint of heart. The relationship to your iPod, your keyboard and your mouse could suffer permanently. Please only scroll down when you are absolutely sure that you are ready to do so.


















Last changes: 05/23/2011