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45-622: Big Walker Lookout is a 100 feet (30 m) observation tower located in the Blue Ridge Highlands Region atop Big Walker Mountain in Bland County , Virginia. The tower is accessed from the Big Walker General Store, just off US Route 52 about 12 miles (19 km) from Wytheville, Virginia . The first store building burned in 2003 and a new store was built just to the right of the first. Originally, visitors crossed to

90-509: A flag pole at its top. Some of these towers are permanently accessible, either free or with the payment of an admission fee. Others are accessible only at certain times, in most cases only with the payment of an admission fee. At these towers the platform is usually open, with some having a restaurant in the basement. There are also towers with a much more extensive use; for example. the observation tower on Rossberg mountains in Reutlingen contains

135-733: A full 360 degree range of vision to conduct long distance observations . Observation towers are usually at least 20 metres (66 ft) tall and are made from stone, iron, and wood. Many modern towers are also used as TV towers, restaurants, or churches. The towers first appeared in the ancient world, as long ago as the Babylonian Empire. Observation towers that are used as guard posts or observation posts over an extended period to overlook an area are commonly called watchtowers instead. Similar instances of observation towers are recognised as crow's nests , observatories , viewing platforms , etc. Observation towers are an easily visible sight on

180-460: A hotel within its structure. Although most of these towers were initially built before World War I , such structures are still being built, in particular as attractions at horticultural shows . Modern observation towers are in most cases no longer built of brick, but concrete, steel and wood are used as the preferred building materials. Permanent observation towers are also sometimes found in amusement parks , however in parks where each attraction

225-515: A lighthouse is usually between 10 and 50 metres high, and is almost always open air. Some sports facilities have high buildings with observation decks. This is often the case at ski jumps, as these have a tower and are usually unused in the summer. In addition, there are other sports facilities with observation decks, like the inclined tower of the Montreal Olympic stadium. Access to the platform of nearly all sports facilities with observation deck

270-402: A restaurant. The height of these platforms, which can be glassed or open-air depending on the height of the building, where they are most common on the topmost floor. As a rule access usually requires the payment of an admission fee, is possible by elevator only at dedicated opening times. Also numerous water towers have, a usually open-air observation deck opened for public traffic, whose height

315-428: A rule an elevator is available in these buildings for the visitors of the observation deck, as the observation deck lies usually very highly (mostly within the range between 50 and 200 metres, at some towers also more highly). Many of these towers have also a tower restaurant, which can be designed as revolving restaurant. While tower restaurants for the protection of the restaurant guests from the wind are in closed rooms,

360-609: A rule, since these buildings are mostly not higher than 20 metres. Active watch towers are not as a rule accessible to the public, since they usually serve for the monitoring of sensitive ranges. However watch towers can be quite ordered for forest fire monitoring a platform accessible for the public or be used during times without forest fire risk as observation towers. Shut down watch towers can however be easily converted to observation towers. Also some radio towers were so built that they can be used apart from their function as transmitting tower also as observation tower. A condition for this

405-433: A t-antenna for medium wave and stands on insulators. However one notices at the first experimental transmissions that at the tower voltages would arise, which would have unpleasant consequences for visitors and so the tower was grounded by the elevator shaft. However this shifted direction of main beam of transmitter away from actual supply area, the city of Berlin. As before World War II nearly whole radio traffic took place in

450-428: Is a considerable amount of lawful unlicensed activity (cordless phones, wireless networking) clustered around 900 MHz and 2.4 GHz, regulated under Title 47 CFR Part 15 . These ISM bands —frequencies with a higher unlicensed power permitted for use originally by Industrial, Scientific, Medical apparatus—are now some of the most crowded in the spectrum because they are open to everyone. The 2.45 GHz frequency

495-489: Is a stop on Virginia Birding and Wildlife Trail's Big Walker Loop. Birds sighted at the Big Walker Lookout include: wild turkey ; black vultures; bald eagles and golden eagles ; American kestrels ; peregrine falcons ; and sharp-shinned , Cooper's hawks , broad-winged , and red-tailed hawks . Observation tower An observation tower is a structure used to view events from a long distance and to create

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540-669: Is a sufficiently stable construction, which permits a permanent safe visitor entrance without interruption of the transmission services. This is the case for towers for radio services in the UHF/VHF-range the case, not however for most types of radio towers for long and medium wave, why a use of these structures as observation tower is impossible in most cases. That the use of a tower as radio tower for medium wave and observation tower not well fits, showed up in Radio Tower Berlin , which originally carried together with an 80 metres high mast

585-530: Is for cellphones , allowing handheld mobile phones be connected to the public switched telephone network and the Internet . Current 3G and 4G cellular networks use UHF, the frequencies varying among different carriers and countries. Satellite phones also use this frequency in the L band and S band . UHF channels are used for digital television broadcasting on both over the air channels and cable television channels . Since 1962, UHF channel tuners (at

630-436: Is in contrast to the entrance of the church usually only possible under payment an admission fee at the opening times of the church. The height of the observation decks is usually in the range between 20 and 50 metres. The platform is nearly always open-air. Some lighthouses have an observation deck open to the public. Access is usually by stairs. An admission fee is often charged and hours may be limited. The observation deck of

675-486: Is mostly as the height of older observation towers in the height range between 10 and 50 metres. It can be reached depending upon tower by stairs or by an elevator. Some water towers have also a tower restaurant. Prospect platforms of water towers are nearly only accessible under payment during the opening times, which are different for each tower. Also some church towers possess observation decks. However elevators are only available in rare cases. The entrance of this platform

720-427: Is not separately paid for, panorama rides are preferred. Watch towers are observation towers, on which persons supervise a larger area. Strictly speaking, control towers also fall into this category, although surveillance from these structures is mostly done in a non-optical way using Radar . Watch towers usually have a closed pulpit to protect the observer against bad weather. Watch towers do not have an elevator as

765-551: Is only possible during opening times after paying an admission fee. Depending upon the building the access can be done by an elevator and/or a stairway. The platforms can be vitreous or open. The height above ground lies usually between 10 and 50 metres. Fire lookout towers have been used widely in Australia, Canada, and the United States to hoist fire lookout persons to heights where they can identify and report new wildfires. In

810-572: Is the beginning of a Virginia Civil War Trails driving tour detailing the Battle of Wytheville , which occurred on July 18, 1863, when "a Federal raiding party marched to the Wytheville area intending to destroy the Virginia and Tennessee Railroad tracks and bridges". Troops also hoped to destroy key telegraph lines and damage nearby salt mines and lead mines. Thanks in part to the warnings brought by Tynes,

855-452: Is the standard for use by microwave ovens , adjacent to the frequencies allocated for Bluetooth network devices. The spectrum from 806 MHz to 890 MHz (UHF channels 70 to 83) was taken away from TV broadcast services in 1983, primarily for analog mobile telephony . In 2009, as part of the transition from analog to digital over-the-air broadcast of television , the spectrum from 698 MHz to 806 MHz (UHF channels 52 to 69)

900-877: The Henninger Turm , a grain silo with tower restaurant and observation deck in Frankfurt, the bell tower of Berlin Olympic stadium , whose platform is accessible by an elevator, the winding tower of the mining industry museum in Bochum, which has an open-air observation deck to which an elevator runs or a wind turbine in Holtriem wind park, which is equipped with a closed platform accessible over stairs. Also aerial tramway support towers, which serve as observation tower (and aerial tramway station), were realized, like Torre Jaume I in Barcelona. Even on

945-498: The UHF / VHF range ( FM sound broadcasting , TV, public rural broadcasting service, and portable radio service). In some cases this usage of the tower is at least as important as its use as an observation tower. Such towers are usually called TV towers or telecommunication towers. Many towers are also equipped with a tower restaurant and allow visitors access via elevators. Also common is the usage of water towers as observation towers. As in

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990-494: The wavelengths of UHF waves are comparable to the size of buildings, trees, vehicles and other common objects, reflection and diffraction from these objects can cause fading due to multipath propagation , especially in built-up urban areas. Atmospheric moisture reduces, or attenuates , the strength of UHF signals over long distances, and the attenuation increases with frequency. UHF TV signals are generally more degraded by moisture than lower bands, such as VHF TV signals. As

1035-617: The ITU UHF band: the L band between 1 and 2 GHz and the S band between 2 and 4 GHz. Radio waves in the UHF band travel almost entirely by line-of-sight propagation (LOS) and ground reflection; unlike in the HF band there is little to no reflection from the ionosphere ( skywave propagation), or ground wave . UHF radio waves are blocked by hills and cannot travel beyond the horizon, but can penetrate foliage and buildings for indoor reception. Since

1080-469: The UHF spectrum is used worldwide for land mobile radio systems, two-way radios used for voice communication for commercial, industrial, public safety, and military purposes. Examples of personal radio services are GMRS , PMR446 , and UHF CB . The most rapidly-expanding use of the band is Wi-Fi ( wireless LAN ) networks in homes, offices, and public places. Wi-Fi IEEE 802.11 low band operates between 2412 and 2484 MHz. A second widespread use

1125-417: The United States, there once were over 5,000 fire lookout towers. Areas where birdlife congregates are often associated with bird observation towers to assist with viewing. Hyperboloid structures have a hyperboloid shape that is usually lattice framework and an observation deck on top. There are also some very different observation towers, which don't fit into other categories. Examples for this are

1170-784: The atmosphere warms and cools throughout the day. The length of an antenna is related to the length of the radio waves used. Due to the short wavelengths, UHF antennas are conveniently stubby and short; at UHF frequencies a quarter-wave monopole , the most common omnidirectional antenna is between 2.5 and 25 cm long. UHF wavelengths are short enough that efficient transmitting antennas are small enough to mount on handheld and mobile devices, so these frequencies are used for two-way land mobile radio systems , such as walkie-talkies , two-way radios in vehicles, and for portable wireless devices ; cordless phones and cell phones . Omnidirectional UHF antennas used on mobile devices are usually short whips , sleeve dipoles , rubber ducky antennas or

1215-461: The battle was largely unsuccessful for the Union forces. "After some skirmishing and confusion on the advance, Union Col. John Toland ordered his men into Wytheville. Hastily organized Confederate resistance succeeded in killing Toland in the street and limiting the damage to the railroad track and stock. The raid did not succeed in its mission as the track was quickly repaired". Big Walker Lookout Tower

1260-674: The case of TV towers the visitor will usually reach the observation deck by elevator, which is usually at a lower height above ground The typical height of the observation deck of water towers is 20 metres up to 50 metres, while the typical height of the platform of TV towers is from 80 metres up to 200 metres. Finally, some church towers may have observation decks, albeit often without an elevator. Many other buildings may have towers which allow for observation. In particular prior to World War I rambler associations, and some municipalities, built observation towers on numerous summits. Usually these towers were built of stone, however sometimes wood or iron

1305-465: The countryside, as they must rise over trees and other obstacles to ensure clear vision. Older control rooms have often been likened to medieval chambers. The heavy use of stone, iron, and wood in their construction helps to create this illusion. Modern towers frequently have observation decks or terraces with restaurants or on the roof of mountain stations of an aerial ropeway. Frequently observation towers are used also as location of radio services within

1350-457: The desire existed to provide these towers with a tower restaurant and an observation deck, in order to make the building of towers more economical via admission fees and increased notability. Several water towers were also built with this in mind, but many have not survived to the modern day. Ultra high frequency Ultra high frequency ( UHF ) is the ITU designation for radio frequencies in

1395-533: The elevator in the late 19th century made taller observation decks possible. Most notably, the Eiffel Tower and the Blackpool Tower were built in this era. Radio towers developed as combined sending and observation tower between 1924 and 1926 in the city of Berlin . After World War II , a great need for tall observation towers arose, due to their dual usage as television and radio transmitters. In large cities,

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1440-464: The long -, medium and shortwave range, first after World War II with introduction of radio services in UHF/VHF-range required towers only acting as antenna carriers, radio towers with observation decks built. For this the closed reinforced concrete construction way was nearly always used. Radio towers with observation decks often serve for TV transmission or for radio relay link services and are called therefore usually TV tower or telecommunication tower. As

1485-483: The planar inverted F antenna (PIFA) used in cellphones. Higher gain omnidirectional UHF antennas can be made of collinear arrays of dipoles and are used for mobile base stations and cellular base station antennas . The short wavelengths also allow high gain antennas to be conveniently small. High gain antennas for point-to-point communication links and UHF television reception are usually Yagi , log periodic , corner reflectors , or reflective array antennas . At

1530-417: The prospect platform can be open or in a closed room. An open platform is more favourable for photographing, since no reflexes at the disk arise, while closed platforms are for many visitors more pleasant. Prospect outlooks on TV towers are opened only at certain times and their entrance is possible only under payment of an admission fee. Also numerous highrise buildings have observation decks , sometimes even

1575-505: The pylons of suspension bridges were already observation decks installed, as the example of Nový Most in Bratislava shows. A very unusual observation tower is Pont basculant de la Seyne-sur-Mer . It was once a bascule bridge, now permanently put upright and used as observation tower. In Germany, observation towers first appeared on the countryside at the end of the 18th century. These early towers were often built by wealthy aristocrats . It

1620-551: The range between 300  megahertz (MHz) and 3  gigahertz (GHz), also known as the decimetre band as the wavelengths range from one meter to one tenth of a meter (one decimeter ). Radio waves with frequencies above the UHF band fall into the super-high frequency (SHF) or microwave frequency range. Lower frequency signals fall into the VHF ( very high frequency ) or lower bands. UHF radio waves propagate mainly by line of sight ; they are blocked by hills and large buildings although

1665-414: The slot antenna or reflective array antenna are used: the slotted cylinder, zig-zag, and panel antennas. UHF television broadcasting channels are used for digital television , although much of the former bandwidth has been reallocated to land mobile radio system , trunked radio and mobile telephone use. Since at UHF frequencies transmitting antennas are small enough to install on portable devices,

1710-517: The time, channels 14 to 83) have been required in television receivers by the All-Channel Receiver Act . However, because of their more limited range, and because few sets could receive them until older sets were replaced, UHF channels were less desirable to broadcasters than VHF channels (and licenses sold for lower prices). A complete list of US Television Frequency allocations can be found at Pan-American television frequencies . There

1755-399: The top end of the band, slot antennas and parabolic dishes become practical. For satellite communication, helical and turnstile antennas are used since satellites typically employ circular polarization which is not sensitive to the relative orientation of the transmitting and receiving antennas. For television broadcasting specialized vertical radiators that are mostly modifications of

1800-447: The tower by way of a swinging bridge that connected to the back of the old general store . The swinging bridge was not destroyed in the fire and still stands. Visitors can cross to the edge where the original staircase connected to the bridge. Big Walker Lookout hosts traditional arts demonstrations on weekends. The lookout tower is open to the public with payment of an admission fee. Located at an elevation of 3,405 feet (1,038 m),

1845-460: The transmission through building walls is strong enough for indoor reception. They are used for television broadcasting , cell phones , satellite communication including GPS , personal radio services including Wi-Fi and Bluetooth , walkie-talkies , cordless phones , satellite phones , and numerous other applications. The IEEE defines the UHF radar band as frequencies between 300 MHz and 1 GHz. Two other IEEE radar bands overlap

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1890-564: The view from the top of the tower encompasses mountain peaks in five different states. The tower was originally built in 1947 and has been run continuously by the Kime family. According to the Virginia Department of Tourism, the tower is located at a mountain pass used by Molly Tynes, a woman who warned the town of Wytheville of impending raids by John Toland during the Civil War . The tower

1935-485: The visual horizon sets the maximum range of UHF transmission to between 30 and 40 miles (48 to 64 km) or less, depending on local terrain, the same frequency channels can be reused by other users in neighboring geographic areas ( frequency reuse ). Radio repeaters are used to retransmit UHF signals when a distance greater than the line of sight is required. Occasionally when conditions are right, UHF radio waves can travel long distances by tropospheric ducting as

1980-657: Was also used. At nearly all these towers access to the observation deck , usually at a height of between 5 and 40 metres, is only possible by way of stairs. Most of these towers are used only for tourism, however some of these towers might also be used, at times of high forest fire risk, as fire observation posts or in times of war as military observation posts with anti-aircraft positions placed beside it. Further uses were not intended at most of these buildings, although some of these towers today now carry antennas for police/fire engine radios, portable radio or low power FM- and TV-transmitters. Older observation towers frequently have

2025-510: Was not until the mid-19th century that citizens took control of the construction of such towers. In Austria and Switzerland many observation towers were established by alpine and tourist associations, and continue to be cared for by them. In the Waldigen Mountains , many citizen committees were active. Because of the long reign of emperor Franz Joseph , many observation decks carry the name "anniversary observation platform". The invention of

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