What´s an EGR Valve?

Citing from about.com:

EGR Valve = Exhaust Gas Recirculation Valve.

The EGR valve helps your car more efficiently and completely burn fuel by recirculating a portion of your exhaust and running it through the combustion process again. This results in a cooler, more complete burn of the fuel which decreases you car's noxious emissions by prohibiting the formation of some harmful gases.

Rough idle and poor acceleration can be caused by a faulty EGR valve. When the EGR valve goes bad, it must be cleaned or replaced.

My 2002 Renault Clio dCI has about 115.000 kilometers and I haven´t found any ERG valve fault symptoms, but I think that´s time to do some cleaning work before it goes wrong ;) These are some photos of the process...


Valve before cleaning...


... and after cleaning.

I´ve just downloaded a new open market (no branded) firmware version (L760XXGK1) to my Samsung SGH-L760, but I haven´t found any significant changes on it. Maybe a better battery level accuracy and slightly improved menu speed, but I haven´t tested it enought to find something really new.

Note: It´s easy to get lost when trying to find new software versions, so here is some useful information about Samsung firmware codes. Let´s take the SGH-L760 new firmware as example, e.g.: L760XXGK1

The firmware code is split into individual sections:

L760 - > model designation (SGH-L760).
XX - > region / network carrier designation (XX = Spain - open Market).
G - > release year (E = 2007).
K - > release month (K = November).
1 - > version number.

Description of some region / network carrier designations:

- Region codes (open Market):

BD Cyprus, Greece
CP Finland
DB Vietnam
DC Thailand
DD India
DT Australia
DX Indonesia, Malaysia, Philippines, Singapore, Vietnam
DZ Malaysia, Singapore
JA South Africa
JC Algeria, Morocco, Nigeria, South Africa, Tunisia
JP Arabic
JR Arabic
JV Algeria, Egypt, Iran, Iraq, Kuwait, Morocco, Nigeria, Oman, Pakistan,
Saudi Arabia,South Africa, Syria, Tunisia, Turkey
MT Switzerland
XA Austria, France, Germany, Italy, Netherlands, Switzerland, United Kingdom
XB Denmark, Norway, Sweden
XC Portugal, Spain
XD Croatia, Czech, Hungary, Slovakia
XE Bulgaria, Estonia, Kazakhstan, Latvia, Lithuania, Russia, Ukraine
XF Bulgaria, Croatia, Romania
XX Austria, Belgium, France, Germany, Hungary, Italy, Spain, United Kingdom
ZC China, Hong Kong
ZH Hong Kong
ZT Taiwan

- Network carrier codes:

AE SFR, France
AI Tim, Italy
AM Vodafone
AN E-Plus, Germany
AO O2
AS KPN, Netherland
AU Mobilkom, Austria
BB Tmn, Portugal
BF Optimus, Portugal
BG Telefonica, Spain
BM Swisscom, Switzerland
BN Amena, Spain
BO T-Mobile, Germany
BU Vodafone
BV Orange, Switzerland
BW O2, United Kingdom
CD Proximus, Belgium
CG Telia Mobitel, Sweden
CH SingTel, Singapore
CK Tele2 Comviq, Sweden
CT Tdc, Denmark
CU One, Austria
CV Telenor, Norway
DT Optus, Australia
DV Telstra, Australia
EF Celcom, Malaysia
JB Vodacom, South Africa
MD Telia Sonera, Finland
MJ Vodafone, Italy
MM Tele Ring, Austria
MV NetCom, Norway
NA Nrj, France
NB Tele2 Norway, Norway
NE H3g Nordic, Sweden
NP H3g, Italy
SS Vodafone, Japan

Release years:

D = 2004
E = 2005
F = 2006
G = 2007
H = 2008

Release months:

A = January
B = February
C = March
D = April
E = May
F = June
G = July
H = August
I = September
J = October
K = November
L = December

Note about "EDGE" (Enhanced Data Rates for GSM Evolution) terminals: The SGH-D600E is an "EDGE" mobile phone. "EDGE" firmware codes have an "E" between model and region / network carrier designation. By example: a D600EBOFA2 firmware code denotes a SGH-D600E T-Mobile version.

WARNING!!! The reprogramming process described below can damage your mobile phone permanently. I write it only for informational purposes. Use this information as your own risk. NOTE: Your phone stored contacts and messages are lost in the reprogramming process, so don´t forget to make a backup to the SIM card before start.



One thing that I hate from mobile communication companies is the habit of branding the embedded firmware of its terminals: they put (or remove) options, themes, melodies and services that don´t appear in the original phone firmware. Recently, I get a Samsung SGH-L760 terminal from spanish operator Movistar with a very customized firmware, that looks awful compared with the original manufacturer´s black themed firmware.



This opinion about mobile phone branding is shared by a lot of users, and for sometime now, have appeared a lot of internet communities dedicated to mobile phone firmware modding and reprogramming. Using this forums as information sources, is very easy to find the programming software and firmware image files required to restore a mobile phone to its original form. Once your mobile has been debranded, you will notice all the menu systems are clearer, unrestricted, and often faster too.

In this case, to replace the Samsung SGH-L760 software we need this things:

- Samsung SGH-L760 mobile phone (obviously!).
- Samsung SGH-L760 USB data transfer cable (included in the phone package).
- Samsung SGH-L760 bundled software CD-ROM (included in the phone package).
- Microsoft Windows XP SP2 PC.
- MultiLoader programming software v.5.30.
- Samsung SGH-L760 original firmware image files (v.L760XXGH2).

And follow this steps carefully:

- Install USB data transfer cable drivers from bundled software CD-ROM.
- Unpack the original firmware image files to a temporary folder.
- Unpack the MultiLoader programming software to another temporary folder.
- Remove SIM card from mobile phone.
- Remove SD memory storage card from mobile phone (if installed).
- Check the battery is fully charged
- Connect the USB data transfer cable to the phone side.
- Launch MultiLoader programming software.
- Power on the mobile phone while the "*" key is pressed.
- The "DOWNLOAD" word appears on the mobile phone screen.
- Connect the USB data transfer cable to the PC USB port side.
- MultiLoader detects automatically the phone COM port.
- Set MultiLoader "MSM6245/MSM6260" option check.
- Set MultiLoader "Boot Change" check.
- Set MultiLoader "Full Download" check.
- Set MultiLoader "Boot" path to "BOOTFILES" folder on the original firmware image files folder.
- Set MultiLoader "Modem" path to "amss.bin" file on the original firmware image files folder.
- Set MultiLoader "Rsrc1" path to "Rsrc.rc1" file on the original firmware image files folder.
- Set MultiLoader "Rsrc2" path to "Rsrc2.rc2" file on the original firmware image files folder.
- Set MultiLoader "Factory FS" path to "FactoryFS.ffs" file on the original firmware image files folder.
- Press the MultiLoader "Download" button to start phone programming.
- Once finished, the phone will reboot.
- A "Rebuilding filesystem" message appears on the mobile phone screen.
- Once finished, the phone will reboot again and starts the new debranded original software version.

It´s done. You only have to reconfigure your settings (preferences and operator MMS/Internet connection parameters) and your phone is ready to go. The Samsung original theme is sleek and elegant ;)

I´ve just finished Halo 3 for Xbox 360, and there´s only one thing to say: Thanks Bungie for make such a brilliant game. Graphics, story, art, sound... every game department has been carefully polished and the result is nothing more than superb. A great end for the trilogy: The Fight has been finished.




Now playing on Xbox 360: Lost Planet: Extreme Condition.

WARNING!!! The process described below is very complicated and can damage your PSP permanently. I write it only for informational purposes and it´s only focused in the hardware modification side.




Some weeks ago, my brother ask me to install a "custom firmware" on his PSP. A "custom firmware" replaces the PSP factory firmware allowing a user to load homebrew software and game backup copies from the memory stick slot. Currently, this "custom firmware" is being developed by an excellent PSP developer known as DarkAlex.

Background Information.

To install a "custom firmware" we need to put the PSP on "service mode". In this mode, the PSP can load executable programs on boot from a memory stick special position in the filesystem. This process is used by Sony service to repair firmware damaged PSPs, and thanks to the PSP developers around the globe, we can use it to replace the factory firmware.

To put the PSP on "service mode" we need a special battery know as "Pandora´s battery". All PSP batteries have a serial number that is read on PSP boot. When the PSP founds the "pandora´s battery" special serial number (all bits to 1), it gets into "service mode" and tries to load code from memory stick. Happily, we can convert our stock PSP battery to a "Pandora´s battery" using a simple trick. If we disable the battery EEPROM that stores the serial number (among other information), the PSP defaults to read all serial number bits to 1, putting the PSP into "service mode" automatically.

Go for it!

So, we are going to disconnect the PSP battery EEPROM. We have to access inside the battery by removing the two glued covers using a flat screwdriver. Be careful not to damage the lithium cells when disassembling the cover (the cells can even explode if they are drilled!).


Disconnect (desolder) the lithium cell pads to shutdown the IC power. This prevents from making an accidental short circuit when manipulating the battery board.


Disconnect the EEPROM ground pin using a 15W iron with a 0,5mm. tip. Lift the pin up carefully so it doesn't break apart ;) Once we have done this, we can solder the board and the cell pads together again and close the battery cover with electrical tape (i know that is not a very elegant solution ;) ).



Now, we have to create the special formatted memory stick and put on it all the needed software to reflash the PSP. There´s a lot of all-in-one programs and web pages describing the process to create a "magic memory stick", so with a bit of googling I´m sure you can find all you need.

Power on the PSP using the power adapter (with the battery removed). Once the boot process is completed, insert the battery. This resets the battery status and the "Pandora´s battery" becomes functional.

Power off the PSP and remove the power adapter. Power on the PSP again with the battery and the "magic memory stick" inserted. If everything goes OK, the PSP will boot the software that you installed in the memory stick to downgrade, upgrade, reinstall or recover the PSP firmware. To back the modified battery to normal mode, you only have to reconnect the lifted EEPROM chip pin to the ground cell pad using a thin wire.

Last year, I bought a Canon Canoscan 8600F flatbed scanner to restore my old family photos, and after all this time, I can say that it was one of the best purchases I´ve do. I´m very happy with it. This beautiful machine can achieve great resolutions (up to 4800 x 9600dpi) and superb color/contrast levels in every scanned original. Canon software lets you to tweak almost every aspect of the scanning process and can reduce original scratches and dust efficiently. But it can´t do miracles and sometimes, we need some Photoshop magic. See this 24x35mm. scanned original and the final image after some retouching work. Nice result!

Some time ago, a friend of mine gave me a small embedded computer that was completely useless for him. This pretty noiseless machine, was normally used as on board computer in some vehicles, and now, I want to make a small home server from it. It features an Intel Pentium III Coppermine processor, 128MB. RAM and a 10GB. HDD. Not too much, but just enough to run a small Debian Linux web/file server. But first, I have to deal with some weird proprietary peripheral connectors. One of them is this 15-pin SUB-D socket:


As you can see, it integrates a variety of signals in only one socket. My objective is to split the PS2 Keyboard/Mouse signals in two 6-pin female Mini-DIN connectors (standard PS2 connectors). Normally, a 6-pin female Mini-DIN PS2 connector has this pinout:


With this pin to signal layout:

1 - Data
2 - (Reserved)
3 - GND
4 - +5v (VCC)
5 - Clock
6 - (Reserved)

The "reserved" pins are not used, so it´s easy to establish a signal-to-signal correspondence between proprietary connector and the two new PS2 connectors. Only I have to buy some components from my electronics supply store and start to connect each signal to its assigned pin. Pretty straightforward...



Now, I can use my PS2 keyboard and mouse without problems.

This is one example of good intentions and bad skills. Someone tried to fix this Motorola V3X USB power connector using a mix of cyanoacrylate (a.k.a. Super Glue) and solder, resulting a disaster. To repair the phone, first we have to reach the motheboard: To do this, take apart both battery and cover. Remove the four visible screws. Remove the bottom cover using a small flat screwdriver (it´s pressure locked). Remove the two new visible screws.


Next, smoothly remove the black frame (it´s pressure locked too) and take apart the motherboard from the phone body removing first the screen connector. Now we can inspect the USB port directly and see how much damage we have.


We remove the cyanoacrylate with the help of a hobby blade and a small flat screwdriver. Using iron and a desoldering pump, desolder the USB connector. We have to remove the solder excess all over. Clean the surfaces with a cotton swab stick or brush impregnated in alcohol. Get a new connector replacement (see RS Components) and solder it to motherboard.


Check connections with the help of a tester and put everything back together. If nothing goes wrong, we have a V3X phone charging again. Not a bad day ;)