service codes for samsung,hp,lexmark,brothers,dell printers

HP Laser Printer

The most common technique used in HP Laser Printer is to use cold resetting. Once cold resetting is done, the printer settings are restored to default factory levels. What needs to be kept in mind while using cold resetting is that the settings in the control panel of the printer

Motherboard routine maintenance of 23 cases

Today, more and more integrated motherboard, motherboard repair has become increasingly difficult, often using specialized digital testing equipment to complete. However, some motherboards do not require specialized common faults detection equipment, your own hands can be resolved, following are some of the most typical example of a motherboard failure repair and hope that everyone will learn the basic approach to solve the motherboard failure.

BASIC ELECTRONIS (TRANSISTOR WORKS)

Transistor is a control component, is mainly used to control the current size, in order to take as an example common-emitter (signal from the base input, the output from the collector, emitter grounded), when the base voltage UB has a slight change in when the base current IB will follow a small change in base current IB under the control of the collector current IC will be a big change, the greater the base current IB, the greater the collector current IC, On the contrary, the smaller the base current, collector current is also smaller, that is, the base current controls the collector current changes. However, the changes in collector current than the changes in base current is much greater, which is the amplification transistor. Changes in IC volume and the change in the ratio of IB is called the transistor magnification β (β = ΔIC / ΔIB, Δ, said variation.), Transistor magnification β is usually in the tens to hundreds of times.

PC Power Supply Knowledge

PC into the system, each component has a single source of power - is the power supply. Power supply must be uninterrupted for all the equipment to provide a stable, continuous current. If the excess or shortage of power supply, the connected device may not function properly, looks like the same as bad. For example, the memory can not be refreshed, resulting in data loss will lead to software errors; the CPU may be deadlock, or randomly re-start; hard disk may not turn, can not be normal processing control signals. Since so many devices and power are closely related, then the power supply as a PC system, the most important components is anything but over. Looking at statistics from the computer failures, power failures part of the total failure rate is very high percentage.

LAPTOP Inverter Fault Detection Method

LCD panel for high voltage power supply to the lamp power supply, it will transform the high-frequency DC low-voltage power supply high voltage power supply to light the lamp, belonging to power conversion devices, easy to heat, it is easier bad. There are many customer's screen dark, and incredibly anxious, thinking that bad screen, or the host goes wrong, drugs everywhere, grasping side asked did not know that that is a small high-pressure plate is broken!

Motherboard Power chip detection method

In general a bad power supply board is now a great possibility heart tablets, power broken heart pieces, CPU in general non-temperature, then you can file with the digital multimeter's diode test inductor and the earth off, if the multimeter calls out resistance on the long - words, power is a good heart piece, if the inductor to ground short circuit, motherboards, power supply part of the problem is absolutely, first regulation on the motherboard there are several take down power transistor, if the inductor is shorted, then the motherboard power supply chip is absolutely heart broken! But also regulate the power transistor is broken

Motherboard failure and Maintenance Basics

A key component of the motherboard is the computer used to connect a variety of computer equipment, the computer plays a vital role. If the board fails, your computer can not properly used. At present more and more integrated motherboard, motherboard repair has become increasingly difficult, often using specialized digital testing equipment to complete, but the control board and comprehensive maintenance technology, the rapid failure investigation board is still very necessary.

BIOS BEEP CODES

BIOS beep meaning

Here's the more common of the three kinds of BIOS (AMI BIOS, Award BIOS and Phoenix BIOS) of computer -
Cases to introduce the Power On Self Test Beep Codes for a specific meaning (on the computer BIOS to use models from the BIOS
Power On Self Test on a chip or from the information to see the words they see AMI compared with AMI BIOS; as they are
Compared to the Award characters Award BIOS).

How can I tell the computer hardware failure?

First, let's look at the computer startup process
1, stored in ROM (read-only memory) in the Bootstrap Loader program, and self-diagnostic program moved to the RAM (random access memory) in the.
2, with the Bootstrap Loader operation, stored in the auxiliary memory devices in the operating system files will be sent to RAM.

HP Laserjets -Service Mode

HP Laserjet 8000, 8100, and 8150 Series service mode

1. Hold down SELECT and JOB CANCEL while powering on the printer, until all lights are illuminated and the Display is blank. (If the Display Panel reads INTERNAL TEST at this point, the keys were released too soon. Repeat this step until successful.)

Nokia Mobile Phone Tips and tricks

These Nokia codes will work on most Nokia Mobile Phones,
Code Description
*3370# Activate Enhanced Full Rate Codec (EFR) - Your phone uses the best sound quality but talk time is reduced my approx. 5%

#3370# Deactivate Enhanced Full Rate Codec (EFR)