Cleaning and drying a smartphone that has fallen into water: Eg. the NEXUS 5X

To repair wet electronic boards , like a mobile that has entered him water, as this Nexus 5X that, despite rapid action he took water by charging connector, speakers and hole cards, it is best use pure alcohol or distilled water and an ultrasound machine , in addition to rub with a soft brush on the visible parts (and still no full guarantees, as if you were running shorts could damage a chip).

If you do not want to complicate , and you have 30 or 50 € which typically charge for repairing these problems, better take it to a repair center phones with good professionals, you will leave no trace of water or debris and running (but do not light after the accident), or try the Waterrevive liquid (which works very well if turned off immediately).

But if the water has not reached penetrate into the metal lids of the base plate (where sensitive to interference electronics is hidden), we can obtain very good results without ultrasound machine with brush and distilled water or alcohol (alcohol It has the advantage that evaporates easily later).

Waterrevive : A couple of young Spaniards have developed a liquid that promises that your phone back up and running in 98% of cases, they say. This liquid (possibly alcohol, distilled water or other solvent of mineral salts) introduced displaces water (containing mineral salts) preventing depositing causing short circuiting. Using this system has good result if we turned off / disconnected the battery quickly, before the lime and salt is deposited. If that system will not work, you can try these indications (100% of cases so far) .

Connecting an IDE (DVD-ROM, HD, etc) unit to a motherboard without IDE port (SATAS only)

Using an IDE-USB adapter we could "recycle" the IDE recorder

In many current motherboards like Gigabyte GA-F2A55M-DS2, no longer include IDE ports , which have been displaced for speed and economy by SATA. 
But if we have such an old IDE DVD Burner 3.5" and we want to continue using it (it is not the time to pull something that works), we can be forced to pay more for a motherboard with those ports, or instead we can place a IDE to USB adapter that functionality allowing us permanently for 4 € (saving us 30 € that costs a new DVD recorder).

As we saw in a previous post , adapters SATA / IDE to USB are very practical; it specifically has to IDE 3.5 "and 2.5" SATA port, very useful when you need to connect hard drives without opening the computer:

You can buy on Ebay from 3.99 shipping included in Spain

We just need build or search for a USB connector on motherboard, which I believe to be the most difficult part (although you can use a box of a PC to go to waste); I for example have obtained one cutting the Firewire 1394 connections (in the first picture the gray cables cut) not be used for anything, and solder the red, white, green and black USB adapter cable at positions corresponding to leave permanently connected to the motherboard:

In the picture below, the adapter connected and working, although I had to remove a lateral from the connector for the power supply on the left:

The plotter fails to recognize the cartridge: Repairing a 500-800 HP Designjet 42 "

We had a problem with our plotter; it marked "unrecognized cartridge" error before finishing of each printed plan; when we repositioned the cartridge the problem was solved for a while, but it seemed a problem of poor contact with the cartridge chip (it was produced when the motor axis ink supply was activated).

To repair it, you have to access the module cartridges; first of all we need to remove the cover of Control, it is a matter of finding and removing all the screws, simple task and which information is on the internet, so that I refrain from commenting;)

Repair of electronic tracks on an old keyboard: Conductive silver liquid

In this post we will repair CNC keyboard that is no longer being manufactured

Contacts on the keyboards have evolved from mechanical systems to more modern with membrane. In this case we will repair an intermediate type; this keyboard from a Gemini 8050T FAGOR around 15 years old carries a screen printed aluminum membrane for tracks and graphite contacts, on which a metal piece with flexible concave shape closes the contact when pressed.

The technology of switches on keyboards usually are of two types: contact , where some kind of spring (metal or plastic or flexible rubber, etc) keeps separate tracks of the conductive surface (graphite or other) of the button, which when pressed blend tracks; and secondly, the induction, where pressing the button, a small magnet creates a small electrical pulse in the coil of the membrane (ultra durable modern musical keyboards).

Repairing first type of keyboards often requires all your ability of "handyman"; some with copper tracks like TV remotes are often easier to repair welding on the tracks a small micro-switch if the button is completely useless, but most cases are plastic membranes that can not be welded and we can use either glue threads on them as in this entry, or use the useful liquid silver, and you will always get a more professional work to build the appropriate cable connections.

Equipment needed

1. Cutter to open the damaged contact (in other keyboards will not be necessary).
2. Cleaning liquid or solvent which does not attack the material of the keyboard; I used Ardrox 9PR5 or you could use isopropyl alcohol.
3. Liquid silver conductive, with which "will draw" deleted / damaged tracks with a fine brush after cleaning them well.
4. A tester to verify that the track drawn conducts electricity.
5. Scissors, PVC tape to cover the contact again, brush, permanent marker to draw the button again, etc.

Your smartphone autorestarts, you lose data? Possible problem, internal memory damaged on your smartphone

I had a Samsung Galaxy SCL i9003 began to malfunction; I just restarted, lost contacts, program settings, etc. 
After searching the web, it turned out that the internal FLASH memory chip, using, being of low quality, began to fail. 

Such memories theoretically not lose their data for up to 10 years, but if damaged by use (allow a limited number of cycles, about 100,000 or more), you may not withhold good data and "forget" . It can happen to any phone that uses them, and sooner or later any "smartphone", tablet, ebook, etc with internal flash now have this problem.

To check it, it is best to use this freeware program h2testw . We connect the phone in "mass storage" mode and run mode continuous writing and then read until an error appears, checking the box for "endless verify" (to select target drive select):

Get visual output from your Arduino with only 2 resistors (and a screen with Video-in)

We just need a TV-Out cable and a pair of resistors (1K and 470 Ohms) and use the library ofmdmetzle@gmail.com to show the output we want through video on any screen. 

Quite simply, no added circuitry.

Is not this just great? The simplicity to power ...

The timing and signal connections to Arduino

This video explains in detail:

How to Build a battery for a Krautkramer USM 25 ultrasound equipment

Krautkramer USM 25 ( source )

Today was the challenge ahead: Search spare parts for rechargeable NI-MH battery 4.8V of anultrasound machine Krautkramer USM 25 Nr. 35274. 

The price for a spare rechargeable battery from the brand owner, GE, was outrageous, so I had to find a way to manufacture it and save good money. This battery is disarmed: 

It has 4 rechargeable batteries 1.2 V each; 1.2 * 4 = 4.8 Volts, wrapped in plastic and a PVC tube outside

The problem I couln´t find the appropiate battery with those measures; about 43 mm. . x Ø22 mm, but thanks to wikipedia and looking at types of batteries , I located your name: Sub C.

It's funny, because it takes a piece of PVC to separate one of them, I guess to make it harder to replace (spare parts worth their thing). And they go into a plasticized PVC cartridge.

Installing the USB driver for Arduino Leonardo in Windows 7 32-bit

The open source electronic board Arduino Leonardo

Yesterday I could try an electronic board that will accompany me for a long time in all my projects; the open source electronic board Arduino (Leonardo model with more inputs / outputs). 
This plate, if you like the "Do It Yourself" is impressive: 

• Cheap (from 20 €)
• Modern, comprehensive and flexible, with 20-pin I / O for highly complex projects
• Open Hardware and Software (no secrets, you can make yourself the pieces)
• Easy to program (using high-level language based on Processing )
• With many examples and an ever larger community
• Very economical and complete, Have I said it yet? XD

If you want to know more about how was this wonder of electronics, nothing better than "Arduino The Documentary" . A demonstration of the power of open source and collaborative altruism: 



Let's go to the topic ... It cost me a lot to find how to install the USB driver for Windows 7 32-bit; I could'nt get it to work, did not find it, despite following the official guide . 

What to do if you drop your mobile into water

First, stay calm and act quickly, take it out of the water and remove the battery, the chances of recovering a long time is decreased if the battery; internal short circuit could be damaging and irrecoverable watching it later.

Then it is best to disarm as much as possible (there are numerous online manuals how to disarm the different terminals) and give heat with a hair, but not too hot as to melt XD.

If you act fast, you will probably only get wet surface. Remove the battery, and if you see it completely dry inside, you can dry it with a hairdryer. You were lucky this time! XD

(This document was translated using Google Translator from the original spanish article)

Once disarmed (without battery or SIM and memory card and lost everything you can) you can opt for the easy solution, which gives a result most of the time, which is putting it in a closed rice for several days container, at least one week if you have not disarmed lot, or at least 3 days if you separate all the pieces, until it is dry. Rice is the desiccant (moisture absorbing) cheaper there.