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A communications tower full of a variety of antennas stands out against a deep, blue, clear sky background.
military radar air on a warship
control pole with camera and megaphone
Old railway signal on heritage railway, Corfe Castle, England. Summer in Britain brings out the colours of the countryside and sunlight lifts the hues and shades of natural stone and architecture in the quaint and tranquil villages of England
Tower, equipped with mobile radio antennas, on a wooded mountain. The dangerous radiation is made visible by transparent symbols.
Communications station and antennae on top of the summit of Serra de Santa Barbara, the highest point of Terceira Island, Azores, Portugal
Camera surveillance for traffic monitoring
 Tornado Siren
Radio telescopes silhouette pointing at the sky at dusk. Radio antenna dishes of the radio telescope against the sunset sky. Satellite dishes against the colored sky for the concept of receiving and sending a signal
View from the Wasserkuppe to the Heidelstein in the Rhoen
Top of military  surveillance tower with array of cameras and a radar dish.  You are being watched.
Tower, equipped with mobile radio antennas, on a wooded mountain. The radiation is made visible by transparent symbols.
Young child waiting to cross the street.
A black and white shot of traffic lights looking opposite directions
Security cameras near government buildings
Back side of cantilevered traffic signal on clear day.
Microwave transmitter / receiver on cellphone communications mast.
Antenna-like measuring instruments for research and development. Rural area in front of a forest.
view of the sumare antennas in rio de Janeiro, brazil.
A phone communications microwave tower in Colorado Springs Colorado
Communication problems. The mobile phone antenna radiates luminous radio waves against a dark sky.
On Punta Helbronner, in the Mont Blanc Massif, there is a receiving-transmitting  and a weather station.
Red lit thin traffic light on city road with clear blue sky
Aviation Radio Navigation Beacon Milky Way Galaxy Night Landscape - Dark sky with billions of stars visible astrophotography.
Greenbrier Radio Telescope, West Virginia
Antenna sending waves
view of the sumare antennas in rio de Janeiro, brazil.
Star Trails behind silhouetted towers. Okayama, Japan. February 2015
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