Sunday, April 18, 2010

ElecTronic Cigrates

Electronic cigarette

An electronic cigarette, also known as an e-cigarette or personal vaporizer, is a battery-powered device that provides inhaled doses of nicotine by way of a vaporized solution. It is an alternative to smoked tobacco products, such as cigarettes, cigars, or pipes. In addition to purported nicotine delivery,[1] this vapor also provides a flavor and physical sensation similar to that of inhaled tobacco smoke, while no tobacco, smoke, or combustion is actually involved in its operation.

An electronic cigarette usually takes the form of some manner of elongated tube, though many are designed to resemble the outward appearance of real smoking products, like cigarettes, cigars, and pipes. Another common design is the "pen-style", so named for its visual resemblance to a ballpoint pen. Most electronic cigarettes are reusable devices with replaceable and refillable parts. A number of disposable electronic cigarettes have also been developed.
Mouthpiece ("cartridge")

The mouthpiece is a small disposable plastic cup-like piece affixed to the end of the tube. Inside the mouthpiece is a smaller plastic cup which holds an absorbent material that is saturated with a flavored liquid solution that may contain nicotine.[3] This inner cup is made such that air is able to flow around it and through a hole in the end of the outer piece; this is necessary for the device to provide the ability for suction to move the vapor into the user's mouth. The mouthpiece is referred to in the industry as a "cartridge". When the liquid in the cartridge has been depleted, it can either be refilled by the user or replaced with another pre-filled cartridge.
Another alternative to using cartridges is the direct dripping method. By removing the absorbent material, one is able to simply remove the plastic mouthpiece and drip several drops of e-liquid directly onto the atomizer bridge. To further ease dripping, some manufacturers have created specialty mouthpieces made of stainless steel or plastic that are intended just for dripping and do not require removal each time you drip.

Heating element ("atomizer")

The heating element serves to vaporize the liquid in the mouthpiece so that it can be inhaled. This component is referred to in the industry as an "atomizer". Some models combine an atomizer and pre-filled cartridge into one disposable component referred to as a "cartomizer"





Battery and electronics

Most electronic cigarettes employ a lithium-ion rechargeable battery to power the heating element. Battery life varies depending on the battery type and size, frequency of use, and operating environment. Many different battery charger types are available, such as wall outlet, car, and USB chargers. The battery is generally the largest component of an electronic cigarette.

Some electronic cigarettes employ an electronic airflow sensor to automatically activate the heating element upon inhalation, while other models require the user to press a button while inhaling. Various other electronic circuits are usually employed as well, such as a timed cutoff switch to prevent overheating and a colored LED to signal activation of the device.
Traditionally, electronic cigarettes have utilized an electronic means of activation. This involved the use of small tactile switches, vacuum switches and the related wiring and electronics necessary to run them. Users soon discovered these could be unreliable. With the advent of "mods", several manufacturer's have created all mechanical electronic cigarettes that eliminate the use of any wiring, solder or electronics in an effort to improve switch reliability.

While some larger electronic cigarette models employ a user-replaceable standard-size battery cell, many models are too small to house a standard-size cell and instead require a proprietary component made by the electronic cigarette manufacturer. For those models, the battery and electronic components are housed within a single replaceable part, which is still generally referred to in the industry simply as the "battery".

FM Transmitter


This circuit uses a small microphone to capture the sound and some transistors to generate radio waves that can be picked up by a FM receiver like a car stereo.

How it Works:

From left to right, the first part is the microphone and some resistors to get it working. Next we have a capacitor and the first transistor, this amplifies the sound from the microphone so that it can be loud enough to work with. The last part, there is a transistor, a coil and some capacitors. This part generates the radio waves and combines them with the sound from the mic to transmit it thru the antenna.
The coil is made with about 9 turns of wire, use a pencil to get the right diameter for the coil. The capacitor with the arrow is called a trimmer capacitor, it has a small screw to adjust the value, we'll use it to tune a certain frequency or station to transmit on.

This Led chaser is built using some very common digital logic circuits. Easy to build, easy to work with, and looks amazing in the dark. This circuit will light each led in sequence, creating a moving light illusion.

How it Works:

From left to right, the first IC is a binary counter, 74ls163, that is used to generate the address numbers we are going to use in the second part of the circuit, the demultiplexer 74ls138. This demux is the core of the circuit, as this IC pulls low the pin selected in the address inputs. Note that you need an external clock for the counter to work (count).

This is a very simple circuit to build, just take note of the control pins on each IC, since both have enable inputs for counting or output, but once set you don't need to worry about them. It can also be extended to 16 leds by using the Q3 output of the counter to control the enable inputs of a second demultiplexer, or just add a second one to generate a double pattern.

Saturday, April 17, 2010

Led Flasher Corcuit


This circuit is built around one of the most popular timer integrated circuits, the 555 timer.

This circuit will flash the led on and of at regular intervals.

How it Work

From left to right, the two resistors and the capacitor set the time it takes to turn the led on or off, by changing the time it takes to charge the capacitor to trigger the timer. Next is the 555 timer, this is where all the work gets done to determine the time the led stays on and off. It contains a complicated circuit inside, but since it is packaged in the IC it can be used as a simple component.
The two capacitors that are right of the timer are just accessories so to speak, but are needed for the timer to work correctly. The last part is the resistor and the led, the resistor is there to limit the current on the led so that it won't burn.
The LED Metronome is a modern interpretation of a classic device which is a staple of music teachers, students and composers everywhere. This circuit uses 12 LEDs to simulate the sweeping motion of the pendulum and a speaker with a simple amplifier to generate a tick as the LEDs at the end of the arc are struck. It is adjustable from about 40 BPM to just over 200 BPM. When made in a Lexan or Plexiglass case it can add a fun ultra-modern touch to music practice (though most music teachers agree that you should never rely on a metronome to keep your beat).

Analog Circuits


Most analog electronic appliances, such as radio receivers, are constructed from combinations of a few types of basic circuits. Analog circuits use a continuous range of voltage as opposed to discrete levels as in digital circuits.

The number of different analog circuits so far devised is huge, especially because a 'circuit' can be defined as anything from a single component, to systems containing thousands of components.

Analog circuits are sometimes called linear circuits although many non-linear effects are used in analog circuits such as mixers, modulators, etc. Good examples of analog circuits include vacuum tube and transistor amplifiers, operational amplifiers and oscillators.

One rarely finds modern circuits that are entirely analog. These days analog circuitry may use digital or even microprocessor techniques to improve performance. This type of circuit is usually called "mixed signal" rather than analog or digital.

Sometimes it may be difficult to differentiate between analog and digital circuits as they have elements of both linear and non-linear operation. An example is the comparator which takes in a continuous range of voltage but only outputs one of two levels as in a digital circuit. Similarly, an overdriven transistor amplifier can take on the characteristics of a controlled switch having essentially two levels of output.

How RAM and Mother Board WorK


If you've ever taken the case off of a computer, you've seen the one piece of equipment that ties everything together -- the motherboard. A motherboard allows all the parts of your computer to receive power and communicate with one another.

Motherboards have come a long way in the­ last twenty years. The first motherboards held very few actual components. The first IBM PC motherboard had only a processor and card slots. Users plugged components like floppy drive controllers and memory into the slots. Today, motherboardstypically boast a wide variety of built-in features, and they directly affect a computer's capabilities and potential for upgrades.

How RAM Works

Random access memory (RAM) is the best known form of computer memory. RAM is considered "random access" because you can access any memory cell directly if you know the row and column that intersect at that cell.

The opposite of RAM is serial access memory (SAM). SAM stores data as a series of memory cells that can only be accessed sequentially (like a cassette tape). If the data is not in the current location, each memory cell is checked until the needed data is found. SAM works very well for memory buffers, where the data is normally stored in the order in which it will be used (a good example is the texture buffer memory on a video card). RAM data, on the other hand, can be accessed in any order. Dynamic Ram This refresh operation is where dynamic RAM gets its name. Dynamic RAM has to be dynamically refreshed all of the time or it forgets what it is holding. The downside of all of this refreshing is that it takes time and slows down the memory.