Making electronics help? (electrical engineering)?

Question

Hi,
ok so i'm a HS student who is interested in electrical engineering.
I want to get a feel of wht it is so as to better ensure if this is wht i want to do for a living.
I'm quite taken with robotics and making "gadgets."

My question is how hard would it be to make a calculator with an LCD color screen (or just any kind)?how expensive would it be?

I've seen tutorials online but they more or less just sell u a kit and it appears tht it cost well over a 100 dollars!
Does anyone know of any good sites tht offer tutorials on how to make inexpensive educational (as in learning abt how to use electricity and make) robots?

what would i all need in order to make one?
Thanks for any input!

Answer 1

it depends on what you plan on doing, since you seem to like electronics/mechatronics, i would recommend getting familiar with microcontrollers. you can easily interface LCD character display as output. you can get development kits for as little as $20-50.



for example check www.mouser.com, www.digykey.com etc

for example Atmel Butterfly kit is only about $20.

http://ca.mouser.com/catalog/catalogUSD/642/195.pdf

Answer 2

About 20-40 years ago electronics went through a transition, with the manufacture of ICs that can perform the function of complicated circuits. Before that, a circuit consisted of a bunch of transistors or tubes, resistors, capacitors, and perhaps some small ICs, etc, and could be easily built at home. And understood by hobbyists.



But with ICs, most circuits/appliances today are just a few ICs connected together, with a keyboard and display, both of which are also controlled by ICs also. The actual circuit is just a bunch of PC traces connecting the IC's together.



So what I'm saying, building kits doesn't get you any knowledge, except experience in soldering and trouble shooting.



If you wanted to build a calculator from simple logic chips, like NAND gates and flip-flops, that is possible, but it will take one huge amount of work, several hundred gates, and lots of debugging, all to duplicate what costs $1 in wall-mart. If you ever get it to work.



But there are other things besides calculators. Don't forget that that $1 calculator is better than a multi-million dollar computer of the WWII era.



Look into timers, audio amplifiers, etc.



.

Answer 3

Early on, you would have designed the calculator with logic elements like OR, AND, and XOR gates. Now these elements are parts of design libraries for programmable elements like gate arrays. If I was going to build a calculator today, I'd probably build it around a micro-controller with interfaces to the keypad and the display. I suspect that an advanced calculator like the HP 50g uses this approach.



Beyond the actual circuit design, there would also be the mechanical challenges of laying out the circuit board, and routing the traces. There are computer aided drafting (CAD) tools to help with this.



Then you'd have to get the multi-layer circuit board made, drilled, and plated. Due to the density of the leads on devices, many are mounted to the board with adhesive solder paste, and then the whole assembly is heated to melt the solder. There are tools you can buy to do this, but in commercial applications, the processes are much better controlled.



Your robot would not only have a controlling computer, controllers for the limbs and wheels driven by motors or solenoids, but also some means of sensing its environment. This is a much more challenging and expensive proposition.