Some Electronics Components

The book I read to research this post was Electronic Project Building for Beginners by RA Penfold which is an excellent book which I had from maplins.

Resistors are one of the most popular components & are used to step the current & voltage down so as to protect a component. Resistance is measured in ohms.

Capacitors store electricity often only briefly & this again is to protect a component. Capacitance is measured in farads although in practise it’s often micro-farads.

There are various forms of diode but there job is to only allow the current to flow one way. A more complex diode and often consists of several diodes is a rectifier. There is no official definition of a rectifier.

Transistors act as a junction for electric current. There are various types of transistors.

Potentiometers are variable resistors.

You can have variable capacitors as well.

Switches open or close a circuit. Relays are a mechanical form of a switch.

Photo cells can come in diode, transistor or resistor form and are influenced by the amount of light.

A meter in a circuit will often be an ammeter.

Often in electronics you will buy a small circuit rather than individual components & then connect that up to a larger circuit.

 

home technology pt 13

Telephone wiring is fitted in either series wiring or a star configuration.  The parts of a telephone network are  structured wiring outlet jacks distribution blocks & phones. Modular jacks are common in most homes. In newer homes they are often flush mounted. A KSU based telephone system has its own controller & the phones can be used as intercoms.

home technology pt 12

Each area that shares a common video signal is in the same video area.  You must decide on whether a distributed video system supports more than one zone.  Video controls should be placed close to the display device.  The controller types are often wireless ir or rf dedicated device controllers extended ir or rf controllers & ir over coaxial cable.

home technology pt 11

Speakers must be matched to the room size. Other factors are the number of  rooms and the number of speakers in each room.  Larger rooms generally need more power to produce acceptable sound levels.  The speakers may need higher sensitivity where louder volumes are needed.  The placement of speakers is important.  For best sound apply certain principles separation zoning & directionality.

home technology pt 10

Speaker anatomy

Driver vibrates the cone.

Cone – diaphragm- dome is typically made from paper plastic or a flexible metal. As it vibrates it creates sound.

Suspension – surround a ring of flexible material that attaches the cone to the metal frame.

Voice coil these are magnets which as they repel & attract each other results in the cone moving.

home technology pt 9

Wireless networking is a good alternative to wired networking because it saves you the hassle & cost of cabling & wiring. A wireless network adaptor can be either an internal inlay card or an external peripheral device.  A wireless AP is a hub that clusters  wireless network adaptors together & acts as a bridge  to a wired network. A wireless bridge is used to connect 2 or more wlans.

home technology pt 8

A peer to peer network gives users the ability to create shares on the peripheral devices connected to their pcs & to files & folders on their local hard disk drives. Another resource they can share is an  internet connection. Win 2k XP & Vista feature an internet connection sharing feature which converts the central pc into a network router.

home technology pt 7

Most modern pcs include a nic network interface card built into the motherboard.  Networks can be run through the telephone or electrical wiring but need special adaptors. Cat5e or Cat6 UTP wire is most common on wired networks. The most common network devices are hubs switches & routers.  A router combines a hub bridge & switch & performs internet routing.

home technology pt 6

A home computer network is very similiar to any other type of computer network. The main difference is scale. Whereas a business computer network may have hundreds of pcs a home computer network only has a few. The mani parts of a network are hardware & software. The hardware establishes the network but without software it has no life.

home technology pt 5

When doing any kind of electrical work you must note what you’ve done. You must listen carefully to the symptoms before doing any kind of repair work. Cable problems usually result from damage to the cable.  The 2 main tests for faulty cable are wire mapping & time domain reflectometry.  You can also test voltage current resistance & continuity.