A yagi antennaside lobes in a two-dimensional power diagram (schematic, polar diagram)A multiband rotary directional antenna for Amateur Radio use

Discover great deals on the many top brand items available only on eBay!

Antennas

Most simply, an antenna (U.S.) or aerial (UK) is an electronic component designed to transmit or receive radio waves. The words "antenna" and "aerial" are used throughout this article with precisely the same meaning. more...

HomeHome
Accessories & CablesAccessories & Cables
AntennasAntennas
Audio & Speaker CablesAudio & Speaker Cables
Blank Tapes & CDsBlank Tapes & CDs
Brackets, MountsBrackets, Mounts
Cases, StorageCases, Storage
Maintenance & CareMaintenance & Care
ManualsManuals
Other Audio AccessoriesOther Audio Accessories
Other TV AccessorieOther TV Accessorie
RF ModulatorsRF Modulators
Selectors, SwitchersSelectors, Switchers
Surge Protection, FiltrationSurge Protection, Filtration
TV AntennasTV Antennas
TV StandsTV Stands
Video CablesVideo Cables
Video Selectors, SwitchesVideo Selectors, Switches
Wall Mounts & BracketsWall Mounts & Brackets
AmplifiersAmplifiers
CD Players & RecordersCD Players & Recorders
Cassette DecksCassette Decks
CrossoversCrossovers
DVD Players & Recorders DVD Players & Recorders
Digital Music...Digital Music...
Digital Video Recorders, PVRDigital Video Recorders, PVR
EqualizersEqualizers
Headphones, HeadsetsHeadphones, Headsets
Home Audio MiscHome Audio Misc
Home Theater ProjectorsHome Theater Projectors
Home Theater in a Box Home Theater in a Box
KaraokeKaraoke
MiniDisc PlayersMiniDisc Players
OtherOther
PreamplifiersPreamplifiers
ProcessorsProcessors
RadiosRadios
ReceiversReceivers
Remote ControlsRemote Controls
Satellite Radio Satellite Radio
Satellite, Cable TVSatellite, Cable TV
Shelf, Compact SystemsShelf, Compact Systems
Speakers & SubwoofersSpeakers & Subwoofers
Televisions TVTelevisions TV
Tuners, AM/FMTuners, AM/FM
TurntablesTurntables
VCRsVCRs
Vintage ElectronicsVintage Electronics
Wholesale LotsWholesale Lots

More specifically, an antenna is an arrangement of conductors designed to radiate (transmit) an electromagnetic field in response to an applied alternating electromotive force (EMF) and the associated alternating electric current.

Alternatively, if an antenna is placed into an electromagnetic field, that field will induce an alternating current upon the antenna, and EMF between its terminals. See radio frequency induction.

Overview

There are two fundamental types of antennas, which, with reference to a specific three dimensional (usually horizontal or vertical) plane, are either omni-directional (radiate equally in the plane) or directional (radiates more in one direction than in the other). All antennas radiate some energy in all directions but careful construction results in large directivity in certain directions and negligible power radiated in other directions.

By adding additional conducting rods or coils (called elements) and varying their length, spacing, and orientation, an antenna with specific desired properties can be created, such as a Yagi-Uda Antenna (often abbreviated to "Yagi"). Typically, antennas are designed to operate in a relatively narrow frequency range. The design criteria for receiving and transmitting antennas differ slightly, but generally an antenna can receive and transmit equally well. This property is called reciprocity.

The vast majority of antennas are simple vertical rods a quarter of a wavelength long. Such antennas are simple in construction, usually inexpensive, and both radiate in and receive from all horizontal directions (omnidirectional). One limitation of this antenna is that it does not radiate or receive in the direction in which the rod points. This region is called the antenna blind cone or null.

Antennas have practical use for the transmission and reception of radio frequency signals (radio, TV, etc.), which can travel over great distances at the speed of light, and pass through nonconducting walls (although often there is a variable signal reduction depending on the type of wall, and natural rock can be very defective to radio signals).

Antenna parameters

There are several critical parameters that affect an antenna's performance and can be adjusted during the design process. These are resonant frequency, impedance, gain, aperture or radiation pattern, polarization, efficiency and bandwidth. Transmit antennas may also have a maximum power rating, and receive antennas differ in their noise rejection properties.

Resonant frequency

The resonant frequency is related to the electrical length of the antenna. This is usually the physical length of the wire multiplied by the ratio of the speed of wave propagation in the wire. Typically an antenna is tuned for a specific frequency, and is effective for a range of frequencies usually centered on that resonant frequency. However, the other properties of the antenna (especially radiation pattern and impedance) change with frequency, so the antenna's resonant frequency may merely be close to the center frequency of these other more important properties.

Read more at Wikipedia.org


[List your site here Free!]

Radio Audio Cable Adaptor Antenna Double Fakra Din Male Aerial Car AccessoriesRadio Audio Cable Adaptor Antenna Double Fakra Din Male Aerial Car Accessories $9.95 Glossy Black Roof Radio Am/Fm Signal Shark Fin Aerial Antenna Car AccessoriesGlossy Black Roof Radio Am/Fm Signal Shark Fin Aerial Antenna Car Accessories $12.79
Accessories Unlimited, Auppp18, 18 Ft Dual Lead Rg59U Coax Cable With 3 Pl-259'sAccessories Unlimited, Auppp18, 18 Ft Dual Lead Rg59U Coax Cable With 3 Pl-259's $54.95 1* Black Shark Fin Car Roof Antenna Radio Fm/Am Signal Aerial Accessories1* Black Shark Fin Car Roof Antenna Radio Fm/Am Signal Aerial Accessories $12.99
Indoor High Definition Antenna Coaxial Cable Extension – 8 FeetIndoor High Definition Antenna Coaxial Cable Extension – 8 Feet $12.99 2014-2019 Maserati Ghibli S Radio Antenna Filter Cables X3 Oem2014-2019 Maserati Ghibli S Radio Antenna Filter Cables X3 Oem $67.49
Gloss Black Shark Fin Car Roof Antenna Radio Fm/Am Signal Aerial Accessories BaGloss Black Shark Fin Car Roof Antenna Radio Fm/Am Signal Aerial Accessories Ba $9.99 New Motorola Haf4016A Astro Xtl5000 Radio Vehicle Antenna w/Accessories/ManualNew Motorola Haf4016A Astro Xtl5000 Radio Vehicle Antenna w/Accessories/Manual $22.99
1 Shark Fin Antenna Cover Black Radio Fm/Am Signal Booster Decor Car Accessories1 Shark Fin Antenna Cover Black Radio Fm/Am Signal Booster Decor Car Accessories $10.99 2013 Mini Cooper S R56 Accessories Antenna Manuel Cables Map2013 Mini Cooper S R56 Accessories Antenna Manuel Cables Map $69.99
Nreal Air Glasses Black Ar Vr Glasses Smart Glasses 2022 Xr Device Wearable DeviNreal Air Glasses Black Ar Vr Glasses Smart Glasses 2022 Xr Device Wearable Devi $450.00 Antenna Base Repair Fix Kit Radio Mast for Chevrolet Chevy 1999 - 2022 NewAntenna Base Repair Fix Kit Radio Mast for Chevrolet Chevy 1999 - 2022 New $19.95
Car Radio Antenna Adapter Audio Cable Dual Fakra Din Male Aerial Accessories 12VCar Radio Antenna Adapter Audio Cable Dual Fakra Din Male Aerial Accessories 12V $11.66 Fin Roof Car Antenna Black Shark Radio Fm/Am Antena Cover Accessories UniversalFin Roof Car Antenna Black Shark Radio Fm/Am Antena Cover Accessories Universal $7.98
+ Lot Oem Motorola Accessories Base Chargers Cables Adapters Antennas Clips Huge+ Lot Oem Motorola Accessories Base Chargers Cables Adapters Antennas Clips Huge $119.95 Gm Oem 84000725 Navigation Radio Antenna Cable Kit for 2015 Silverado SierraGm Oem 84000725 Navigation Radio Antenna Cable Kit for 2015 Silverado Sierra $455.99
4 Pack 6Ft Charging Cable For iPhone Multicolor4 Pack 6Ft Charging Cable For iPhone Multicolor $11.39 K40 Antennas & Accessories 18' Super Mini-8 Cb Antenna Cable with Removable FmeK40 Antennas & Accessories 18' Super Mini-8 Cb Antenna Cable with Removable Fme $32.38
Vintage Gemini Tv/Fm 2 Set Coupler Vhf - Fm #Tv41 Antennas AccessoriesVintage Gemini Tv/Fm 2 Set Coupler Vhf - Fm #Tv41 Antennas Accessories $12.00 Dish Player-Dvr 625 with remote, cables, antenna and accessoriesDish Player-Dvr 625 with remote, cables, antenna and accessories $129.99
Antronix Vra901 8+1 Port Amplifier with AccessoriesAntronix Vra901 8+1 Port Amplifier with Accessories $24.99 Car Antenna Aerial Radio Replacement Vehicle W/ 1.3m Cable AccessoriesCar Antenna Aerial Radio Replacement Vehicle W/ 1.3m Cable Accessories $13.84
Accessories Unlimited, Aupll18,18 Ft Dual Lead Coax Cable With A Pl259 & 2 LugsAccessories Unlimited, Aupll18,18 Ft Dual Lead Coax Cable With A Pl259 & 2 Lugs $48.95 Accessories Shark Fin Roof Antenna Aerial Am/Fm Radio Signal Decoration Car TrimAccessories Shark Fin Roof Antenna Aerial Am/Fm Radio Signal Decoration Car Trim $13.99
Parts Accessories Car Shark Fin Roof Antenna Aerial Fm/Am Radio Signal UniversalParts Accessories Car Shark Fin Roof Antenna Aerial Fm/Am Radio Signal Universal $45.95 Universal Car Hidden Amplified Antenna Kit 12V Electronic Stereo Am/Fm Radio NewUniversal Car Hidden Amplified Antenna Kit 12V Electronic Stereo Am/Fm Radio New $18.95
Large lot of used vintage cables Amplifier Antenna Ham Radio Cb And AccessoriesLarge lot of used vintage cables Amplifier Antenna Ham Radio Cb And Accessories $34.99 New K40 Antennas & Accessories K4018fme Coax CablFme,18 Ft. Free ShippingNew K40 Antennas & Accessories K4018fme Coax CablFme,18 Ft. Free Shipping $26.99
Radio Audio Antenna Cable Adaptor Male Double Fakra-Din Male Aerial AccessoriesRadio Audio Antenna Cable Adaptor Male Double Fakra-Din Male Aerial Accessories $12.59 K40 Antennas & Accessories K4018Fme 18ft Mini-8 Cb Antenna CableK40 Antennas & Accessories K4018Fme 18ft Mini-8 Cb Antenna Cable $33.90
96ct Phone Cable Charger Accessories Wholesale Lot Countertop Display-2 Ports96ct Phone Cable Charger Accessories Wholesale Lot Countertop Display-2 Ports $134.95 Car Radio Audio Cable Adaptor Antenna Double Fakra Din Male Aerial AccessoriesCar Radio Audio Cable Adaptor Antenna Double Fakra Din Male Aerial Accessories $12.59
1x Car Radio Antenna Adapter Audio Cable Dual Fakra Din Male Aerial Accessories1x Car Radio Antenna Adapter Audio Cable Dual Fakra Din Male Aerial Accessories $11.05 Accessories Unlimited Aupl259C Male Uhf Crimp Connector For Rg58 Coax CableAccessories Unlimited Aupl259C Male Uhf Crimp Connector For Rg58 Coax Cable $14.99
96ct Phone Cable Charger Accessories Wholesale Lot Countertop Display96ct Phone Cable Charger Accessories Wholesale Lot Countertop Display $129.95 Accessories Auto Shark Fin Roof Antenna Radio Am/Fm Signal Aerial Car AmplifierAccessories Auto Shark Fin Roof Antenna Radio Am/Fm Signal Aerial Car Amplifier $16.99
Mixed Lot Audio accessories, speaker wires ,Fm antennae, headphones, selector Q2Mixed Lot Audio accessories, speaker wires ,Fm antennae, headphones, selector Q2 $23.60 Metra Aw-Ec144 144 Inch Extension CableMetra Aw-Ec144 144 Inch Extension Cable $14.98
New MobileMark Antenna Solutions Cvw402-2Hm2Hm2Hm00-Blk-12 0 w/Cables/AccessoriesNew MobileMark Antenna Solutions Cvw402-2Hm2Hm2Hm00-Blk-12 0 w/Cables/Accessories $94.99 Allstar Rak-10A Remote Antenna Kit,15 ft. Cable,BracetAllstar Rak-10A Remote Antenna Kit,15 ft. Cable,Bracet $104.92
Corvette C3 Antenna Cable 75E179" Cable 1969-1975Corvette C3 Antenna Cable 75E179" Cable 1969-1975 $41.99 Car Stereo Fm Am Radio Antenna Adapter Cable Fakra Z To Din Replace AccessoriesCar Stereo Fm Am Radio Antenna Adapter Cable Fakra Z To Din Replace Accessories $7.59
Accessories Unlimited, Aupl12, 12 Foot Rg58Au Coax Cable With Pl259 And LugsAccessories Unlimited, Aupl12, 12 Foot Rg58Au Coax Cable With Pl259 And Lugs $29.95 Accessories Unlimited, Aupp12, 12 Ft Rg58Au Coax Cable With Pl259's On Each EndAccessories Unlimited, Aupp12, 12 Ft Rg58Au Coax Cable With Pl259's On Each End $39.95
Car Radio Antenna Adapter Audio Cable Dual Fakra Din Male Aerial Car AccessoriesCar Radio Antenna Adapter Audio Cable Dual Fakra Din Male Aerial Car Accessories $12.55 Universal Cable Receiver 15cm Replacement Replaces Accessories AdapterUniversal Cable Receiver 15cm Replacement Replaces Accessories Adapter $6.44
Universal Black Roof Radio Am/Fm Signal Shark Fin Aerial Antenna Car AccessoriesUniversal Black Roof Radio Am/Fm Signal Shark Fin Aerial Antenna Car Accessories $15.99 22pc Electronic Part Lot Chargers Power Cords Connector Cables Loop Antenna &.22pc Electronic Part Lot Chargers Power Cords Connector Cables Loop Antenna &. $11.99
New Shark Fin Roof Antenna Cover Radio Fm/Am Signal Aerial AccessoriesNew Shark Fin Roof Antenna Cover Radio Fm/Am Signal Aerial Accessories $7.98 Carbon Fiber Shark Fin Car Roof Antenna Radio Fm/Am Signal Aerial AccessoriesCarbon Fiber Shark Fin Car Roof Antenna Radio Fm/Am Signal Aerial Accessories $10.98
K40 Antennas & Accessories K4018fme Coax Cable,Fme Connector,18 Ft.K40 Antennas & Accessories K4018fme Coax Cable,Fme Connector,18 Ft. $25.40 White Fin Roof Car Antenna Aerial Shark Radio Fm/Am Antena Cover Accessories UsWhite Fin Roof Car Antenna Aerial Shark Radio Fm/Am Antena Cover Accessories Us $8.98
Firestik K9A Dual Lead 18' Rg59A/U Coax Cable 3 Pl259 Connectors Single FireFlexFirestik K9A Dual Lead 18' Rg59A/U Coax Cable 3 Pl259 Connectors Single FireFlex $64.99 Csi wireless Gps Md Mini Max 803-0034-05A w/ Mgl-3 Antenna + Cables AccessoriesCsi wireless Gps Md Mini Max 803-0034-05A w/ Mgl-3 Antenna + Cables Accessories $199.95
Click to see more Antennas items at www.ebay.com
Prices current as of last update, 05/27/23 8:50pm.

Home Contact Resources Exchange Links ebay