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Built in 1956 the Crystal Palace transmitter tower was
the tallest building in London at 728 ft until Canary Wharf was built in 1991.
The BBC chose to build a freestanding 'Eiffel Tower' type structure as the
conventional TV mast has to be guyed. This was impossible within the confines
of the Park and local roads. The Tower was built on part of the site of the old
aquarium and probably on the tunnel that led from the old TV studios under
Crystal Palace to the North Tower before both were destroyed.
Initially built to transmit the single BBC 405 line
service the tower has in the past 50 years acquired more and more tenants.
Nearly all London public broadcasters transmit from the Tower with notable
exceptions of Channel 5 analogue (from the old ITV transmitter in Church Road,
South Norwood) and the BBC Radio VHF services from Wrotham in Kent beside the
M20 just before it meets the M26. The Church Road transmitter acts as a standby
for the major channels.
The tower will be the sole hub of London's digital
services when analogue is closed in 2012. A new central shaft is expected to be
built to carry new cables for the extra more powerful transmitters. This will
change the appearance a little but the old profile will stay.
Ownership of the Tower has changed several times in
the past few years. The BBC was forced to divest its transmission services by
Margaret Thatcher's Conservative Government. It was acquired by Crown Castle.
Crown was then acquired by NTL who later sold it to National Grid. It is now
(March 2008) owned by the Australian Macquarie Bank.
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Crystal Palace serves more people than any other
transmitter. It covers most of South East England and TV reception reaches into
the East Midlands and the English Channel. |
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Health Risks
In the early 1970s there was a scare caused by an
apparent cluster of cancer cases around the Sutton Coldfield transmitter near
Birmingham. A study of the much more highly populated area around Crystal
Palace was conducted. This showed that there was a very small decrease in the
expected cases very near the transmitter (radiation is good for you?) and a
small increase in a ring a few miles out. Overall nothing very significant.
However it should be noted that many transmissions are now at shorter
wavelengths making it a candidate for another study.
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