Texas Instruments TI Voyage 200

...I decided to get the Texas Instrument (TI) Voyage 200 as I've always been very happy with my TI calculators in the past.


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What it looks like
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The TI Voyage 200 is about 18cm x 11cm x 2cm (W x H x D) and has a quite attractive shape. As you can see on the product ...
...9x5cm on the left side. This one has a green background whereas the characters are displayed in black. The contrast is very good, you can read everything clearly. The calculator has a weight of about 396g which is ok for its size and functions.
On the right there is a keypad as you know it from all ordinary calculators - the numbers from 0 to 9, brackets, operators, sinus, cosines, pi etc. Above that there are arrow keys as well as some keys ... more

As I'm studying Computer Science / Computer Engineering, I (unfortunately) have to deal with Maths on a nearly daily basis. We are not allowed to use any calculators in the four Maths exams (neither in Electrical Engineering, Physics, Hardware Engineering…) but for home use I wanted to buy myself a calculator to a) control my results (nothing is more annoying than calculating and calculating over several pages and then having to find out that there's a mistake in first few lines) and to b) get a result quickly when I don't have my laptop with my beloved math software around.
After some thinking I decided to get the Texas Instrument (TI) Voyage 200 as I've always been very happy with my TI calculators in the past.

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What it looks like
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The TI Voyage 200 is about 18cm x 11cm x 2cm (W x H x D) and has a quite attractive shape. As you can see on the product photo it is grey and has a big display, sized 9x5cm on the left side. This one has a green background whereas the characters are displayed in black. The contrast is very good, you can read everything clearly. The calculator has a weight of about 396g which is ok for its size and functions.
On the right there is a keypad as you know it from all ordinary calculators - the numbers from 0 to 9, brackets, operators, sinus, cosines, pi etc. Above that there are arrow keys as well as some keys for the control of the calculator.
On the left side you find a keyboard as you know it from your home computer - TI sells this calculator worldwide with the "English" keyboard layout.
The person who designed the layout has well done, the positions of the keys is very cleverly chosen what makes it easy and comfortable to use the calculator. They are quite small, but if you don't have too big hands they are still fine. The only downside: Proper typing won't work on this small keyboard. If accidentally you touch another key while pressing one it won't lead to a wrong input as you have to press down the keys relatively hard.
Most keys have to functions, these are clearly labelled and the position of the functions makes sense.
The calculator comes with a grey transparent cover to protect its surface from scratches and other damages. Furthermore, both, the calculator as well as the cover have four gummy knobs which prevents the calculator from slipping on the table too much.
The connectors for the data cable are on the back of the calculator and are easy to reach. When the cable is plugged in you still can put the table onto the desk. The battery case is on the bottom and is slightly difficult to open, but as you don't have to do that too often it doesn't matter that much.

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technical details
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Technical details - of course - should never completely miss in a review, so here's a list of the most interesting ones.

available ROM: 2,7 MB
available RAM: 188 KB
high resolution display: 128 x 240 Pixel
Processor: 10 MHz
Compatible to all TI-92 software applications
VSC-interface
Connection to the PC via graph link or graph link USB possible
Connection between two calculators is possible
NO serial interface
14 positions (pre- and post decimal positions) for real and complex numbers
batteries: 4 x AAA

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features and functions
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Let's have a look at the features then, shall we? This will probably be the longest part of the review as there are plenty of them - too many to show and explain all of them here.
There are two different groups of features, on the one hand the "normal" functions and on the other hand the functions that are run by installed applications.

~~~ Applications ~~~

When you buy the calculator there are already some pre-installed applications. Those are - depending on the user - more or less useful and relevant. Altogether, the installation of more than 50 programs is possible, where some might be maths related programs, but others games like Tetris. You find them on the internet, they are usually available for free download.
To make it easier to manage all the different applications it is possible to put them into different groups.

Here a short description of the pre-installed applications:

- Cabri Geometry: A geometry software that enables you to draw different forms on the calculator
- CellSheet - This program enables you to interchange data with Microsoft Excel
- Clock: An embedded clock. This clock makes it possible for you to use the calculator as organizer, but also enables you to make time-critical experiments and simulations.
- Data/Matrix Editor: Here you comfortably can create matrices and work with them.
- Finance: An application for finance mathematics
- Graph: Enables you to draw graphs
- Polynomal Root Finder: Finds polynomial roots (numerically)
- Program Editor: An editor for you to write your own applications for your TI Voyage
-Simultaneous Equations Solver: Solves quadratic and non-quadratic equations (numerically)
- Stats/List Editor: Applications for statistics and probability calculations
- Study Cards: An application based on a well known system of learning vocabulary etc. You can embed graphics and texts to study anywhere
- Math Guide: Helps you to calculate and simplify certain types of integrals, derivations, equations of all kinds, polynomial functions or just simple expressions.
The last program is the one I certainly use most often, because you can choose the next step out of a list. That makes the application a great one to find mistakes in the own calculation as you get all extensions. It's also great to try out whether another method leads you to the same result.
-Geometer's Sketchpad: Another geometry application
- TextEditor: A text editor ;-)
Y=Editor: An editor in which you quickly can put in functions which can be automatically drawn.

~~~ Functions ~~~

Apart from that, there are the "normal" functions the calculator knows. Here, on the one hand, I have to mention the "CAS" (Computer Algebra System). It includes (among other things) symbolic infinitesimal calculus and symbolic algebra.
The well-known mathematical functions are - of course - also known by the calculator. On top of it it masters the calculation with complex numbers, the transformation between different number systems (and the calculation with e.g. hexadecimal numbers), hyperbolic and trigonometric calculations etc.
The transformation between unit and the calculation with constants does just as much belong to the range of features as graphical functions (rotation, work with 3D-graphics, graphical design with polar coordinates…) and static functions (histograms, scatter plots, combination and permutation, random numbers…).
Also for the work with matrices the calculator is of much use. Eigen-values, eigen-vectors, matrices with symbolic elements... Certainly a piece of cake - no, not for me, but for the TI Voyage.
And if that's not enough for you yet, it's even possible to define your own functions.

All in all an enormous amount of functions of which hardly anybody needs every single one. And keep in mind: It's only a small selection I've mentioned here now. Even after now nearly two years I'm still surprised what the calculator can do.

To make the use more comfortable, the calculator allows to you change most settings. The language is one of them, but you can also choose the display of the graphs ("function", "parametric", "polar"…), the amount of positions or the unit of angles (radian, degree). Of much use is the possibility to use the screen in split screen modus.

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Price and where to get it
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Those, who now think - phew, this is probably expensive… Are unfortunately right. The price for the calculator is around £170 - £180 (incl. VAT) and if you want extras you'd be charged even more. Whether you want to spend so much money on a calculator - well, that's of course up to you, but I think that the TI Voyage is worth its money IF you need most of the functions. If you just want to add two and two together it's certainly too expensive.

You find the calculator online on amazon.co.uk or www.calculators-online.co.uk , if you want to buy it in a high street shop you might have to search for a while; I haven't seen it anywhere yet.

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Included in delivery…
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If you only order the calculator you will receive the cover as well as a handbook with it, which has 330 pages and is a paperback. In this handbook you find a short introduction into the use of the calculator. But short doesn't always mean bad; this book is really easy to understand, contains a lot of pictures and, to make it short, is very helpful. It also includes a alphabetical list of all functions which enables you to find them quickly.

Apart from that, several accessories are available, which sometimes are sold in bundles with the calculator.

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Accessories
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Very useful and even essential for many users is the USB cable for the connection between the calculator and the computer. With it comes a CD-ROM with software that allows easy data transfer between the two devices.
Furthermore, there is a proper handbook for the calculator. It comes in a set of two books with 1272 pages - for the ridiculous price of about 20 GBP. In my opinion you only need it if you want to work really scientifically. I bought both books but have never really used them as "normal" tasks can be solved without them, the small handbook that is delivered with the calculator is absolutely detailed enough for this purpose.
Then there is a proper keyboard you can connect to the TI Voyage. For people who use the calculator very often useful, because they can type far quicker. For any other user: Far too expensive - more than 40 GBP for a simple keyboard - no, thanks. Especially as you won't type that much.
A cable fort he connection of two calculators can be useful - that's up to you. Sometimes it's delivered with the calculator; just have a look at the offers.
If the computing power is not enough for you, you can buy a SpeedUpMAX-Module. I bought it with my calculator and it already was built in when I got it, so I can't say whether it's necessary. TI promises a twice as big computing power and a 100% quicker file transfer between TI-TI and TI-Computer though.

And last but not least there is plenty of software around. Games like Tetris or hangman are available just as much as useful application for Electrical Engineering. Just have a look around the internet, many programs are freeware.

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Use the calculator
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Now you know that the calculator can do a hell of lot of things. But how easy - or how difficult - is it to use? Do you already have to have completed a degree, just to understand how the calculator is used? The answer is no. Even though the range of functions is enormous, the use of the calculator is still very intuitive and easy.
After having switched the calculator on you find yourself on the home screen. There you see the icons of all installed applications if they are added there (some of the programs you have installed can just be started from the command line whereas all pre-installed applications are found on that screen).
Through pressing the "enter" button you can start each program, with the key "apps" you can go back to the home screen.
The commands in the programs are listed in a menu, which is placed at the top of the screen. To navigate through it you can use the keys F1 to F8 and the number keys, but alternatively the use of the arrow keys is possible.
If you want to calculate something without the help of the applications, you have to change to the so-called calculator screen. There you find the command line for every kind of commands, number, operators, symbols… as well as an area in the upper part of the screen where inputs and results are displayed.
We find the menu here as well, it includes among other things often used commands like "solve" (to solve an equation), "factor" (to factorise an expression), "limit" (to calculate the limits), "define" (to define constants) or "graph" to quickly draw a graph. The commands are copied into the command line when you choose them where they can be completed.
Once you've typed the command in, you just need to press one of the two enter keys and soon you see you input and the results on the screen. With the arrow keys you can scroll through the lines to see older inputs and results, which is especially useful for longer methods.
In case you've forgotten a command for a certain method - or you just can't think of it at the moment - you can have a look at all mathematical functions available, simply through pressing the "catalog" key. (That's not a spelling mistake - it's really spelled the American way on the key…).
The names of the commands are well chosen, so that you often even don't have to bother looking into the handbook to find out what they are doing.
Pressing the "Math" key could also help you in that situation; it also displays the catalogue, but sorted by topics.

The input of commands is, as I've already mentioned, very intuitively. Here are a few examples to give you an impression:

Indefinite integral of 2x-sin(2x)
 (3x-sin(2x), x)

Roots of x²+5x+3
solve(x^2+5x+3=0, x)

input of a three-dimensional matrix
[1, 2, 3; 4, 5, 6; 7, 8, 9]

definition of constants and multiplication of them:
Define x = [1, 2, 3; 4, 5, 6; 7, 8, 9]
Define y = [1, 2, 3; 4, 5, 6; 7, 8, 9]
x*y

Drawing of a graph
Graph 3x+9

Test whether 3 is a prime number
isPrime(3)

All in all very simple, easy to understand and remember - and soon you've got a feeling what commands look like and you hardly ever need to look into your handbook.

From the command line you also can run all installed applications. What commands you need to put in you usually find in the handbooks or readme files that come with the program; I installed Tetris some time ago and just need to type in tetris() to run the game for example.

The format of the calculator is very handy; I usually hold it in my hands and press the numbers on the number pad as well as the symbol keys with the thumb of my right hand. With my left thumb I then can reach the keys on the keyboard, which I hardly ever use though.

Transferring the data from/to the PC is easy as well. After you've started the software (the one you got with the cable) you get a clearly arranged user interface showing the folder tree of your calculator. There you can choose variables you want to delete, the data you want to transfer and much more.
It's also possible to delete the data directly on the calculator which takes far longer though, especially if it's a big amount. But it's still simple - press "var link" to open a list where you can administrate your data. One function there is to delete the data, but it also possible to copy or rename them.

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Conclusion
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Altogether a great calculator with all functions you can think of. If you're studying sciences you certainly can need them, just for school it's a bit too much.
The use is simple, the calculator robust and the batteries work quite long - unless you play a lot of games on it. I've used it from time to time, but also played some games here and there, and the batteries were ok for slightly over a year.
RAM and ROM - the size of either one is adequate. So is the speed, calculations are done very quickly.
Navigation is easy, thanks to function- and arrow keys. A good compromise has been found concerning the size of the calculator and the size of the keys.
The handbook is easy to understand and covers all important topics.

Despite the high price I award five stars as the calculator convinced me completely. 

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