Telescopic Antenna

what is a telescopic antenna ? hw is it diff frm normal antenna ?

wt is the minimum frequency one can detect with such available antennas ? or rather can we detect frequencies in hertz range ?

A telescopic antenna is collapsible. It is a series of small diameter tubes of 6 to 8 inches in length nested one inside the other. The antenna can be extended to its full length or retracted to a small length for storage of portability.

Radio antennas are optimally sized based upon wavelength of the frequency they are expected to “see” . Even multiples of wave length are also used for antennas to minimize there length. i.e. ( 1/2 or 1/4 wavelength)
Antenna wave length (lambda) is base on the speed (c) that a radio signal travels which is about 3×10^8 m/s (300000000 m/s) divided by the frequency (f)

lambda = c / f

Frequencies in the hertz range would have wavelengths in the 1000’s of kilometers range. So any practical length antenna (2 or 3 feet in Length) would work just as well as a larger 5 to 10 foot antenna as the wavelength is so large.

Handheld Radio Telescopic Metal Antenna 450-470MHz $6.28

Telescopic Antenna Single Pin Buckle Sports Watch Walkie Talkie Black Purple $10.62

New Radioshack scanner/ham Center-Loaded Telescoping Whip Antenna $14.00

Telescopic Antenna Adjustable Band Analog Watch Walkie Talkie Black Blue $11.06

Center-Loaded Telescoping Scanner and HAM Radio Whip Antenna $17.99

Telescopic Antenna Single Pin Buckle Sports Watch Walkie Talkie Black Purple $10.01

2 Pcs Telescopic Antenna Flexible Band Analog Watch Walkie Talkie Green Red $13.82

Hand Held Radio 400-470MHz Telescopic Male BNC Antenna $6.28

COBRA HA-TA LONG-DISTANCE TELESCOPING ANTENNA $22.49

Telescopic antenna for Grundig G1000A Shortwave radio $7.45

Telescopic antenna for Grundig YB – 550 Shortwave radio $8.45

Eton G1100 Digital AM/FM Alarm Shortwave Radio W/Telescopic Antenna $83.99

TELESCOPIC 26″ RIGHT ANGLE ALL BAND SCANNER ANTENNA WITH MOTOROLA PLUG $9.00

Replacement Telescopic Metal Antenna for Walkie Talkie $6.28

Children Telescopic Antenna Camouflage Walkie-talkie Interphone Toy Pair $10.74

Telescopic 5 Sections Screw on SMA Connector Antenna $5.24

Fanon Model T808 & T909 Citizens Band Transceiver – Telescoping Antenna *NEW* $9.99

Telescopic Whip Antenna 10 pcs $4.99

Telescopic Whip Antenna 10 pcs $4.99

Telescopic Whip Antenna 10 pcs $4.99

Telescopic 5 Sections Screw on SMA Connector Antenna $5.26

CB 11Meter 27MHz – 28MHz 45.5″ BNC Telescopic Antenna $15.86

Children Telescopic Antenna Camouflage Walkie-talkie Interphone Toy Pair $10.16

LOT OF TELESCOPING ANTENNAS WITH LOAD-LOOK! $7.20

New Nagoya NA-707 SMA-Male 2.15dB 1.8-1800Mhz Telescopic Antenna HT/Scanner $9.50

Telescopic antenna for Grundig G2000A Porsche Shortwave $7.95

Uniden BATY0034001 BC560XLA/560XL Telescopic Antenna $5.00

Telescopic antenna for Eton E-10 Shortwave radio $9.45

Telescopic antenna for Grundig Traveller II Dig,Tr. III $7.45

Telescopic antenna for Grundig Traveller II Analog $7.45

Telescopic antenna for Eton/Grundig E-100/G-100 radio $7.45

Telescopic antenna for Grundig Platinum Traveller $5.95

Lot of 5 telescoping wire antenna’s TV radio tuner $4.99

Telescopic 5 Sections Screw on SMA Connector Antenna $5.27

Cobra Electronics HA-TA Cb Antenna Telescoping Doubles $21.95

Telescopic 5 Sections Screw on SMA Connector Antenna $6.69

HAM RADIO BNC VHF 136-174MHz TELESCOPIC FOLDING ANTENNA $8.00

SMA-MALE SMA-P FOLDING UHF TELESCOPIC ANTENNA $8.00

SMA-MALE SMA-P VHF FOLDING TELESCOPIC ANTENNA $8.00

2 Pcs Telescopic Antenna Flexible Band Analog Watch Walkie Talkie Green Red $14.46

Replacement Telescopic Metal Antenna for Walkie Talkie $6.65

5-021-430 BNC UHF 420-440Mhz TELESCOPIC Antenna $11.00

24″ BNC Telescopic Antenna Ham Amateur Radio 220 – 225MHz 222MHz 1.25Meter Band $8.99

23.5″ Black Whip VHF Telescopic Antenna for Motorola $5.99

28MHz Ham Amateur Radio 10 Meter Band HF BNC QRP Telescopic Antenna $15.99

Telescopic antenna (Black) for Grundig Traveller II Analog $5.95

UNIDEN SCANNER ANTENNA BNC TELESCOPIC * BASE SCANNER* RADIOSHACK – GRE ANY BNC $9.00

24.5″ BNC Telescopic Antenna 150MHz to 160MHz $4.99

COBRA 27.5″ Long-Distance Telescoping Antenna Perfect for Hand Held CB’s #HA-TA $22.00

Telescopic 5 Sections Screw on SMA Connector Antenna $5.65

To see beyond what astronomers can do with traditional telescopes, which have visible light for display, a radio telescope is designed to hear sounds from outer space rather than to monuments. Most designed as a parabolic antenna, a radio telescope allows the user to listen sounds emanating from sources in space.

Most people with an interest in space have probably heard of the search for extraterrestrial Activity (SETA), a group of people to control signals from space with a radio telescope that may indicate life from outer space. To date there has been successful isolation of sounds from space can be attributed to extraterrestrial sources, except of course in movies.

Neutral hydrogen carbon monoxide and examples of radio waves picked up a radio telescope, along with other sources of electromagnetic signals picked up as sound. The telescope first use was in 1937, a plate of about 30 feet in diameter, with growing interest since then and the matrices of the first put to use in the 1950s. Today the largest is the 1894-foot diameter RATAN600 Russia.

From the sound space science fiction Sparks Imagination

With the ability to receive sound signals from space picked up a radio telescope, the imagination of writers and amateur star-watchers have fueled the beliefs of some of the sounds being created by life in space. The argument persists in continuing the existence of life in space and the signs are not easily identified using questionable as indications of extraterrestrial life.

A very large radio telescope dishes in New Mexico has 27 antenna dish, each with a diameter about 82 feet. They work together searching the skies of the sounds, recognizing that given the speed of sound is much slower than the speed of light, any sound picked up could be yesterday or centuries ago.

Under construction in Western Europe is a set of low frequency telescopes radio consisting of 25,000 smaller antennas to develop radio boxes of heaven on the basis of the origins and current location of sound sources captured by the array. The groupings of the antenna covers an area of approximately 220 square miles. With the extra power to pull the radio signals from space it is hoped a better map of the galaxy and nearby galaxies may provide a better understanding of space that was experienced in

About the Author:

Rohit Chopra has written several useful articles on topics like
Telescopes,
Telescope Lens,
Meade Telescope,
Hubble Telescope, etc. Get more useful
information on Telescopes at
http://www.digitalphotographywiz.com

Article Source: ArticlesBase.com – Radio Telescope Lets You Hear Into Space