Right,
lets begin to install the chip.
Take
the wire that you have chosen to use and make sure that you can identify
each wire
individually
as you can't get mixed up later. You can use thicker insulation to
wrap around the wire or number the wire i.e. 1,5,6,8 etc.
When
wring the phone I work from the chip in the phone [we will refer to this
as the EPROM]
to
the pic chip. Simply solder the wire to the legs of eprom as show in the
pictures linked below,
then
place a small bit of installation tape over the eprom to prevent it shorting
out.
Don't
solder the pic chip in yet. With the wire in place you have three main
choices of which way the wire should be routed to the chip, see the
second picture below.
There
are two different EPROM's in some phones, most are 32k and some are 64k.
The
only difference is one can hold more information than the other. Check
and see which type of eprom is in the phone that you are about to chip.
Just look at the eprom on the phone if its a
32k
in should read 24c32, if its a 64k it should read 24c64, or something similar.
For
32k eprom click here.
For
64k eprom click here.
The red line above is one possible way of installing the chip but you have to cut a small hole in the side of the internal plastic casing, I prefer this way as from the outside you can't see any wires or any sign that the phone has been opened.
The blue line is where the wires would come up from the eprom and through a small hole that is mainly for the battery connector, this way is very easy but the wires are visible from the outside when the battery cover is removed.
And last is the yellow line, there is a small hole in the plastic internal casing that the wires can go through, I find this a bit tricky but it works well, I must warn you that there is a screw hole beside it so if you use this way you must be careful not to damage or break the wires when screwing the outer casing back on.
Chose
which way you want to route the wires then we replace the internal case.
Replace
the casing the same way as you removed it before and replace the screw
that connects the two internal casings together. Leave the LCD till the
end.
Now
we have to find a good place to mount the chip, the picture below shows
two locations
that
I use, one is for the surface mount type chip and the other is the through
hole type.
As
you can see the wires come out from which ever way you chose and connected
to the chip.
Before
placing the chip you must cover the area where the chips is to be placed
with a small bit of insulation tape to prevent it shorting out. Solder
the chip using the first picture as a guide to wiring it. When done place
the chip in the one of the above positions and tape it down to prevent
it from moving. Replace the battery connector, then the LCD and then the
two outer cases, screw the cases together, replace the sim and battery
and then move on to the next stage, testing your phone.