Editing Cobra Alarm battery upgrade (section)

=== Dissasembly of Case ===

For dissasembly of the sounder you will need:

#Sharp knife (plasters once you cut yourself!)
#Philips screwdriver number 2
#Soldering Iron
#Solder sucker (if you have one)
#Some solder

Now the dissasembly

#Remove the heatshrink around the cable onto the sounder box with a knife (<i>can get away without doing this, but the wire will be very tight to push through, and there may even be some sealant gumming it up</i>)
#Undo the screws that hold the sounder together and gently pull the sounder apart pushing the wire through the case

==== Inspecting ====

At this point you should be able to decide on whether you need a new battey pack or not, if it is corroding on the ends, I would, at that point send a U2U to '''Nokesy''' and order a new battery at roughly £30 (inc VAT) including postage on an individual battery.

*Below there are some photos of Good Vs Bad PCB's (bad images not uploaded yet).
 
<gallery>
File:IMG 2749b.JPG|Bad Top
File:IMG 2745.JPG|Bad Bottom
</gallery>

If it is like the bad one, go on to "Cleaning", if not go to "Disassembly to fit battery" 

===== Cleaning =====

#Detach all cables from the circuit board and pull out any chips inserted into it. Take note of where each one goes so that they can be properly reinserted after cleaning.
#Pour a quarter-cup of baking soda into a small bowl and add 1 to 2 tablespoons of water until the mixture forms a thick paste.
#Insert a toothbrush into the baking soda paste and apply it onto the corroded parts of the circuit board. Scrub the circuit board gently with the toothbrush to loosen some of the corrosion.
#Allow the paste mixture to sit on the circuit board for 20 to 30 minutes. The paste mixture will dry during this time, which is normal.
#Rinse the circuit board off in clean water to remove all traces of the baking soda.
#Spray the entire surface of the circuit board with a standard household cleaner that does not contain phosphates (Mr Muscle Kitchen Cleaner). Allow the cleaner to sit for 10 to 15 seconds, then scrub the surface of the circuit board with the toothbrush. You don't need to scrub very hard, since you already cleaned it once with the toothbrush.
#Rinse the circuit board again in clean tap water and dry the board using a lint-free towel. Use a blotting motion when drying so as not to damage any of the small components.
#Preheat an oven to 170 degrees, then turn it off and place the circuit board inside. Allow the board to remain in the oven for two to three hours to remove all moisture.
#Reinsert all chips into the circuit board and reattach all cables.

==== Disassembly to fit battery ====

To be written and photo's added!

<gallery>
File:Disassembly1.jpg|disassembly 1
Disassembly2.jpg|disassembly 2
Dissassembly3.jpg|disassembly 3
Dissassembly4.jpg|disassembly 4
Dissassembly5.jpg|disassembly 5
Dissassembly6.jpg|disassembly 6
Cobra-battery.jpg|battery pack - old vs new
Battery Info.jpg|new battery pack specs
</gallery>