Hello everyone.

I have to extract the main idea of the following text, but I’m utterly confused. Take a look:

Computers are electronic machines for processing data. Data are pieces or items of information that have been proper prepared so that the machine can work with them. Processing means handling or manipulating the material that has been presented to the machine in such ways as performing calculations, classifying information or making comparisons. A computer is made of millions of electronic devices that can store the date or switch them through complex circuits with differentes functions at incredible speeds.

The collection of devices that constitute a computer are technically known as a computer system. This system consists of functional components, or parts, for input, storage, control, processing, and output. All general-purpose computer systems has these components, but their physical characteristics may vary

The main storage, control and processing components constitute the heart of the computer system. The central processing unit (CPU) has been designed by the manufacturer to control and carry out basic instructions to that particular computer. It is here that the data processing is done. The C.P.U has two components, called the control and arithmetic units. Input and output are handled by machines that are called I/O devices.

What confuses me is that I do not see a real main idea, except for the components of a computer.
So, what do you think is the main idea? (I have to underline it)

Thanks in advance

I’m going to make this circuit (http://forum.allaboutcircuits.com/attachment.php?attachmentid=13352&d=1257607202) ( A LED lamp using Phone line power, this was found from internet). In this circuit, the well-known LM317T volt regulator is used to control the voltage. However I have a doubt of arrangement of these components. As per the data sheet, In order to control voltage, two resistors need to be used as my 2nd pic(http://forum.allaboutcircuits.com/attachment.php?attachmentid=13351&d=1257607202). So please tell me whether this is correct….. (I’m not an electronic expert..:-( )

I know that the inside of the cube is mostly hollow, and I began to wonder if it was possible to stuff electronic components or wires in there. What I want to know is if there is a way to have the completed state of the cube complete an internal circuit that could trigger an outside action such as turning on a light, either through a transmitter or wired to the cube itself.

I’ve thought about lining the inner sides of the pieces with a thin metal sheet that basically makes a complete current only in the solved state, but I’m not sure how to do it or how practical it would be. And then there’s also the issue of how to trigger that outside action once solved, whether it be through wires running from the cube itself or some form of wireless communication. And finally this has to all fit inside the cube.

My question is: How should I go about doing this, or is this an impossible task without major modification to the cube or a custom built cube? Suggestions?
I just realized that aluminum foil makes a great conduit for the internal wiring system. It’s flat, cheap, and conducts.

I’m still have a lot to learn about electronics and I’m getting there but I’m still having trouble understanding a few concepts.

When building an electronic circuit with components, why would you need to purchase a voltage regulator. From what I understand it keeps a voltage constant

But why wouldn’t you just use some sort of resistor combination to get the voltage you need from a load resistor and just build the rest of your circuit off that.

I’m talking about on a small scale like when building circuits on breadboards.

Hi,

I’m building a simple circuit with two 4000 series logic ICs, an LDR and a buzzer amongst a couple of other things.

I’m not sure what type of capacitors to buy to go in it.
I need a 0.001 mf, a 10mf, and a 100mf capacitor but am not sure what type.

Please could you provide a link from this site:

http://www.rapidonline.com/Electronic-Components/Capacitors

of the type of capacitor I should buy. I am thinking electrolytic?

Thank you very much.

Froskoy.

I already know that a relay is one of the simplest,cheapest and one of the most widely used component in the electrical or electronic world.
what i want to know is;
(1)Why bother to use a small amount of current or voltage to turn on a relay which would eventually control a device that uses far more current than which was used to turn it(relay) on.
Wouldn’t it be easier and less time consuming to connect the device straight to it’s source(supply voltage) thus bypassing any relay.
What is the pros and cons of such a configuration?

Please help with one of my physics homework problems I am very stuck on.

"One of the main factors driving improvements in the cost and complexity of integrated circuits (ICs) is improvements in photolithography and the resulting ability to print ever smaller features. Modern circuits are made using a variety of complicated lithography techniques, with the goal to make electronic traces as small and as close to each other as possible (to reduce the overall size, and thus increase the speed). In the end though, all optical techniques are limited by diffraction.
Assume we have a scannable laser that draws a line on a circuit board (the light exposes a line of photoresist, which then becomes impervious to a subsequent chemical etch, leaving only the narrow metal line under the exposed photoresist). Assume the laser wavelength is 248 nm (Krypton Fluoride excimer laser), the initial beam diameter is 1 cm, and the focusing lens (diameter = 1.3 cm) is extremely ‘fast’, with a focal length of only 0.625 cm."

a) What is the approximate width w of the line (defined here as the distance between diffraction minima on either side of the central spot/ridge — see figure)?

b) What is the minimum resolvable line separation between adjacent lines?

c) If the laser wavelength is instead reduced to 157 nm (as is now potentially available with Argon Fluoride excimer lasers, though technical challenges remain), what is the new minimum resolvable line separation?

d) Assuming the size of the traces is the only constraint limiting the ‘areal density’ (i.e., how many components can be laid out per square centimeter), by what factor does the areal density increase in going from a writing laser with λ = 248 nm to one with λ = 157 nm?

e) Going back to the lithography system with a laser that produces light (in air) at λ = 248 nm, what minimum line separation can be expected in this case (i.e., what is the new answer to b), if the space between the lens and the photoresist is filled with water [n = 1.33 for water])? Hint: What effect does the index have on the wavelength of the light?

I want to run an electronic device that is supplied with a power supply delivering 9vAC @ 3.2 Amps. This device is the fourth in a long generation of similar devices who have used 9vAC @ 700Ma. I was told that the new device has higher output only to supply one new feature (which isn’t even installed on my device) and that using the lower current will be more than adequate to power the LCD screen and other things which are essentially the same as the older models.

Does this sound accurate to you guys?

P.S. the device is an alarm system, with only basic components, just a small circuit board, backup battery, and an LCD screen.

Thanks
The problem is that the new 3.2A transformer doesn’t support X10 technology yet, and GE may not be able to get a 3.2A transformer that is compatible with X10 through the UL approval process anytime soon.

There are transformers with 700ma available for the previous models that already have X10 compatible transformers.

I have a house full of X10 devices and want the newer alarm. Heard it would work from some alarm tech who said he has done it… but wanted to check other sources first.