Casio CFX-9850G / CFX-9850GB + Overclocking Overclocking Tutorial is This How-to it at the Casio CFX-9850G (gray) can all or even almost identical to the CFX-9850GB + (the black) and the CFX-9850C (the be want white and blue). It is in this mod is a really great modification:
This graphic calculators are used mainly in high school and at university and have now reached general popularity, and only the Texas Instruments Voyage 200 or TI 89 + has achieved similar fame . This, however, have both a computer algebra system and go for 100 € and go up the Voyage 200 with 180 € proposes to book.
More gratifying is that one can considerably speed up the little Casio and what I have now written a little guide. The topic is already in many forums and some bloggers had already planned howtos, but never completed. All based on the fact that a small component in the calculator exchanges, indicating in principle the clock, so the speed with which the GTR rates. Standard is a 4 Mhz resonator SMD (or 4.3 to be exact) - A quartz crystal which is applied to a mini-circuit board (hence the word SMD) ... We want this exchange in our tutorial by an 8 MHz resonator SMD! This means 100% performance increase
- a value from the PC overclockers large area make eyes, because you would be happy in the PC sector with 20% ...
What you need for modding? first to be overclocked computer, which I scored on ebay for under 20 € and leaving most of them under 20 €:
well as soldering equipment, this will involve a relatively fine soldering iron with a 10 € soldering iron from the Conrad quite sufficient. It is important that you regularly clean the tip and smooth drag, so you have a good contact to the solder. Contaminated with a soldering iron soldering is a pain, so I took my tip in the course of the mods 3 or 4 times sanded off.
solder, preferably with a soul that serves as a rosin flux and ensures that the solder flows down there, where it should ...
wire, that is, is simply a fine wire with about 1.4 mm ^ 2 is ideal, which is also available at Conrad are for 1.20 € (0.14 LiY RING 10 M YELLOW)
shrink tubing which is heated later with a heat gun so that narrows and makes for perfect isolation:
Desoldering, because you can "soak up" with this solder, or alternatively a Entlötsaugpumpe ... However, dealing with this "little" complicated and is not necessary, but more on that later:
And the real resonator. This time probably become obsolete again and again the sources, which is why I would like to sum me what I was able to learn. Requires
is probably a majority, according to sources
SMD resonator, which determines in principle, only the size, but with normal, large Quartze it seems to have been problems. He also should have a
beat between 4 MHz and 8MHz . 8 MHz made with not all the calculators, so often, a 7.3 MHz resonator recommended. This is nciht always available, why I opted for some 6 MHz and 8 MHz resonators. The additional capacity, an SMD Resonator brings matter seems to be ... but you should always pay attention to the size
! Half of my ordered resonators were
too small, the right people have about 7mm long and 3mm wide. Item number 726459-62 for Conrad, currently costs only 0.36 € a piece ...
addition screwdriver and other accessories ...
Step 1: Open the calculator
mitlerweile should be the first backup made, since a complete loss of data likely is. In addition, you should definitely check regularly on the heating discharge static to prevent fine components are destroyed.
first open the battery compartment, you must at the 9850G model has a screw loose:
remove then all 4 batteries as well as the little coin battery, and remove all marked screws:
should from now on you are your calculator always on the side of the display have time, otherwise verutschen the keys - which, while not a problem because you can simply use the keys again, but this must not be.
Now we come to the tricky part. The GTRs by Snap-ins are closed, that means small plastic hook as we know it from any device. These start at the top of the bottom between the 2 halves with 2 old chip cards, the two halves separate ... Alternatively, very carefully with a screwdriver. The whole is, if one makes it the first time, relatively heavy, but soon you get the hang of it.
If you are all snap have dissolved into, it should look like this:
are the top the two halves of this somewhat complicated "hinges" with plastic connected and you can only use the upper half try gently to pry up. Nciht other way. The 5th Times are open to me now it stopped two plastic nipples but why does the GTR is still optimal.
Step 2: Find the resonator must
own a 9850G now toil even further, the owner of a can or a 9850gb + 9850C jump to Step 3, because there the board is rotated so that the resonator is already visible now.
now have to be solved another 6 screws, do not let it from my tape disturbing is not with you still there;) fold away
Now the display part up, and there is now your cavity in the 9850GB + devices put in the same, just only on the other side the board
Step 3: Remove the old resonator
now must first be labeled X1 resonator soldered. This has 3 contacts which are soldered to each 2 solder points on each side.
One can proceed according to three ways.
You can try by small time-term heating of solder wick and the solder joints on the resonator the used solder to absorb, so you can remove the resonator easy,
We tried all three joints per side to heat the same and increase the resonator with a pair of tweezers.
I decided for option 1, but had to be Ellen, that it is not working as I wanted because I at one point solder in the cavity was.
So I decided to route 3, the violent, irreversible destruction of the old quartz, in which he was careful with ner abkneift pliers. As already 5 of the pads with me were resolved, it was quite simple.
However, one must then throw away the old Quartz ...
Now everything should look like this (up on the already soldered cable)
Step 4:
soldering of the new resonator You can either solder the resonator directly on the board, or as I recommend Short Cable solder and solder it to the resonator.
This strip of 2mm wire, tin it with some solder and then solder the solder joint under the same heat of the cable and the cable.
This now all 3 contacts (which are 2 of the matter, they're connected)
Now you should go shrink tubing over the cables and the heat (with a hot air gun for instance) ... without melting the GTR;)
Now only the fine wire - with the correct polarity to the resonator solder without these rises in flame ... it looks like this:
important here is that the average Pol also associated with the average solder joint, since it is grounded.
Now even shrink tubing or electrical tape to make the resonator and insulate everything well.
Step 5: Closing the
GTRs ... then fix the resonator and the cable somewhere with tape and the GTR back together and all pull screws. Then use all the batteries.
If you did everything right, you should now the GTR I can start on AC.
If not, that was enough for me before, you have to press the small reset button behind:
... However, you must reset this nciht, it was just about to start.
now has your gtr only be still alive ... if not you have probably done something wrong and You shall check all solder joints and sometimes try new batteries (I once had no contact and I thought the worst)
DONE your GTR now expects twice as fast as a normal.
The draw of 10 sine functions (sin (x), sin (2x), ...) takes
old: 54.4 seconds
new: 28.6 seconds ...
accounts for 90% performance increase!
thus has your gtr now 190% of the old power.
However I would like some
cited disadvantages of the mods :
by the higher clock nciht it is possible with another device via the built-in interface to communicate, because voting is no longer here the bars. A connection to the PC by nciht possible. Unless you build the old Quartz an additional and switches with 2 microswitch. However, I need
this function does not necessarily why I have not tried it, but
In this thread has made this one.
addition, the GTR verbaucht probably almost twice the power - he also twice as fast as expected, but has evened out eventually.
also wishes I link to some useful sites:
Marcel's CFX-9850G page which has since gone to sleep but ... and
Marcos Homepage where there are also some nice things to GTR is.
and my Flickr album to Mod ...
I like being open to suggestions and answer questions also like to mod and would be glad if you link to my howto.
