- Disassembly Overview
- Electrostatic Discharge (ESD)
- EMI (Electromagnetic Interference)
- Disassembly
- Tools
- Opening the Case
- Cables and Connectors
- Storage Devices
- Motherboards
- Mobile Device Issues
- Reassembly
- Preventive Maintenance
- Basic Electronics Overview
- Electronics Terms
- Power Supply Overview
- Power Supply Form Factors
- Purposes of a Power Supply
- Power Supply Voltages
- Mobile Device Travel and Storage
- Mobile Device Power
- ACPI (Advanced Configuration and Power Interface)
- Replacing or Upgrading a Power Supply
- Symptoms of Power Supply Problems
- Solving Power Supply Problems
- Adverse Power Conditions
- Adverse Power Protection
- Surge Protectors
- Line Conditioners
- Uninterruptible Power Supply (UPS)
- Standby Power Supply (SPS)
- Phone Line Isolator
- Electrical Fires
- Computer Disposal/Recycling
- Soft Skills?Written Communications Skills
- Chapter Summary
- Key Terms
- Review Questions
- Exercises
- Activities
EMI (Electromagnetic Interference)
EMI (electromagnetic interference, sometimes called EMR, for electromagnetic radiation) is noise caused by electrical devices. Many devices can cause EMI, such as a computer, a pencil sharpener, a motor, a vacuum cleaner, an air conditioner, and fluorescent lighting. The electrical devices around the computer case, including a CRT-type monitor and speakers, cause more problems than the computer.
A specific type of electromagnetic interference that affects computers is RFI (radio frequency interference). RFI is simply those noises that occur in the radio frequency range. Anytime a computer has an intermittent problem, check the surrounding devices for the source of that problem. For example, if the computer goes down only when the pencil sharpener operates or when using the optical drive, EMI could be to blame. EMI problems are very hard to track to the source. Any electronic device including computers and printers can be a source of EMI/RFI. EMI/RFI can affect any electronic circuit. EMI can also come through power lines. Move the computer to a different wall outlet or to a totally different circuit to determine if the power outlet is the problem source. EMI can also affect files on a hard drive.