4G is the next generation of technology that the International Telecommunication Union has created for transferring data via the Internet. The speed is 100 MB/s downstream and 50 MB/s upstream, with a bandwidth of 20 MHz. The idea that used to wield the great value of 4G format that society is consuming more video and heavy images and this will make the mobile phone supports it. A continuación show you a small graphic comparison between 3G and 4G in the most common uses computer-related.

VDC would be the abbreviation for Volt Direct Current which translated would volts direct current. The idea of ??this type is unidirectional current to the load. Direct current is normally produced by batteries, thermocouples, solar cells and a dynamo electric machine type. The direct current can flow in conductors such as wires, but may also flow through semiconductors, insulators ... In the image: 1 - current per pulse 2 - Direct Current (DC) 3 - Alternating Current (AC) 4 - Variable Current

When calculating the life of a battery it will be necessary to know the number of charge cycles that can be performed until the battery does not begin to lose its capacity.
Depending on the type of battery these charging cycles can vary, the most common being the mobile batteries, manufactured Li-Ion or Li-Po, which have a duration of between 300 and 500 charging cycles according to model and manufacturer.
Once thisE limit we will notice how the battery loses duration of operation, arriving to lose up to 25% of its capacity of load.
At this point it will be necessary to evaluate a battery change.
It should be noted that usage and charging habits can significantly affect battery life. For example, factors such as heat, charge the battery several times a day without it is almost exhausted, etc. Will be affectedits duration.
Therefore, to get the most out of the battery we must know when a full charge cycle is performed, and try to avoid misuse of charge, to increase its useful life.
A charging cycle is considered when the battery has been discharged or its 100% charge has been used.
The manufacturers advise that the charge is never made below the 58% battery, since the battery voltage would not fall so lowTo, so you could end up winning up to 4000 charge cycles.
Tips to increase the life of a battery.

• Avoid extreme heat or cold or very long applications of the device.
• Charge the battery as often as you can.
• Fully discharge the battery from time to time.
• Do not let the battery run out completely before charging.

Below is a table with theDifferent voltages (V), charge cycles (C) and battery percentage (B).

The socket is the part that allows connecting the bulb to the socket. There is a wide selection of bushings for different types of bulbs. The nomenclature for each type includes 1 or more letters (type of lampholder), followed by 1 or more numbers (diameter of lampholder).
Example: The bush E27 would correspond to the type of thread E (Edison) of 27mm in diameter.

• E12: Diameter of 12mm, this is a tamYear smaller than the most commonly used standard E27.
• E14: It is the second most common cap, only varies a little of the E27, with a diameter of 14 to 17 mm. It is normally used for bulbs or lamps.
• E27: This is the most common cap. It has a thick cup shape with thread to be able to adapt to the connector. It measures 27mm wide.
• E40: Has a diameter of 40 mm, it is the largest thread of this tIpo.
• G4: With a distance between pins of 4.0 mm. It is a type of cap that is frequently used in appliqués, ceiling lamps and hanging lamps.
• G5.3: With a distance between pins of 5.33 mm. The GU 5.3 socket format is a format widely used in small led floodlights with transformer. Usually used in halogen lamps and dichroic halogens.
• GY6.35: With a distance between pins of 6.35 mm, trOf a model similar to the previous one.
• G9: With a ditancia between pins of 9,0 mm. Usually used for ceiling lamps and hanging lamps.
• G13: With a distance between pins of 12,7 mm. It is used in fluorescent tubes.
• GX53: With distance between pins of 53 mm. Its most common use is the installation in light bulbs to illuminate furniture or unusual places. It does not need transformer.
• GU10: With a distance between10 mm pins. The GU10 bushing shape is a widely used format in small transformerless LED spotlights. Usually used in dichroic halogen lamps.
• B22: Type of bayonet connector used in countries such as Africa, India and Ireland.
• MR16: Its use is normally limited to 12V halogen lamps.