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    Post US Civil Defense (EAN) Early Attack Notification systems 1950 - 1963

    As most of you are probably aware I have a huge collection of US Civil Defense items Constantly on the look out for new stuff to add I was lucky to come across a very rare 1950's Conalert II for sale on e/bay for the princely sum of just £16.00

    It arrived yesterday and although its fairly weathered it powers up ok

    A bit of history on the Early EAN system:

    Early in the 'Cold War', there was concern that enemy bombers could simply home in on American cities by tuning in to specific broadcast radio and television transmitters. At the time, certain 50 kilowatt AM broadcast stations were still clear channel, the only stations in the nation at night on specific frequencies.

    The 1951 solution to the problem was called Conelrad which stood for CONtrol of ELectronic RAdiation. Conelrad was "devised to provide radio communications in a national emergency while denying enemy bombers the use of radio beams as an aid in finding targets. This is accomplished by having television and FM stations cease their regular transmissions and selected AM stations to go to either 640 or 1240 KHz."

    In an alert, with broadcast stations transmitting only on either 640 or 1240 KHz, no directional aid would be available to an enemy bomber. Emergency information for the public would be broadcast on those frequencies. Radios beginning with model year 1953 are marked with little CD triangles at 640 and 1240 on the AM broadcast dial.


    All broadcast stations and even ham radio operators were required to have a means of monitoring and to cease normal transmission in the event of a Conelrad alert. This Conalert II monitor was probably used by a commercial broadcast radio or TV station.
    These monitors were designed to be on at all hours. They were designed to be left on either the 640 or 1240 setting. The red "Conelrad Alarm" pilot light activates when the unit is first turned on. After warmup, it can be "reset" using the momentary contact bat handle switch.

    If a carrier is detected in the 640 or 1240 setting, the alarm lights up. When the remote switch is in the "On" position, the 6 volts AC used by the alarm pilot light is also routed to a rear terminal strip for triggering a remote alarm or light. Remote speaker connections are also available. The three tunable settings labeled A, B, and C were typically set to larger radio stations in the area as a check to see if they were still on the air as a hedge against false triggering of the alarm. The alarm light will stay on if the channel switch is on one of those three "channels".



    CONALERT II dating from 1951 the unit still powers up and I have an original recording of a EAN test broadcast of the time available to scare myself silly



    Originally tuned into Radio KCBS - San Francisco!

    As The 'Cold War' progressed through the 1950's and into the 1960's, technology kept pace! Civil Defense in the 1960's was all about fallout Shelters and how to survive the bomb! Even more so during the Cuban Missile Crisis. Notification of impending attack was one of the primary concerns of the US CD Administration. Sirens were one way, but people in rural areas stiil relied on "Conelrad".

    This system needed up dating as technology advanced. One way to alert people was a novel idea to send a signal down the power lines and alert people to an impending attack
    Enter the NEAR (National Emergency Alarm Repeater)

    Research and testing for the NEAR program was developed in 1956 during the cold war to supplement the existing siren warning system and radio broadcasts in the event of a nuclear attack. The NEAR system had been developed by 1963 but for unspecified reasons, the program went defunct and the devices were destroyed by their respective manufacturers. Those devices that have survived are rare and very collectible. Luckily I found a mint condition one still in its original box
    The price! Don't ask!



    THE alarm plugged into a conventional electrical socket The devices would be set off in an emergency by altering the regular AC signal being generated and transmitted by the local power company, setting off a buzzer and lighting up the triangle

    Normal Civil Defense personnel had there own means of communication and this was usual through local Ham radio, "RACES" (Radio Amateur Civil Emergency Service) or using a Gonset Communicator III which operated on the 6 metre band, this radio had duel voltage and could be powered either by mains, 110 voltage or 12 volt car battery.





    A complete set, Gonset III Communicator with its protective CD bag This set was again another good old e/bay purchase

    By the early 1960's CB radio was becoming available in the US and although the sets were big and heavy and still powered by radio valves, they helped supplement the CD services.



    Gonset G12 communicator circa 1960 CB radio, originally having only 4 channel's.



    Powered by 8 huge radio valves The construction of the valves alone is a work of art



    The radio was heavily vented to allow the dissipation of heat from those 8 valves

    After the development of intercontinental ballistic missiles reduced the likelihood of a bomber attack, CONELRAD was replaced by the Emergency Broadcast System on August 5, 1963, which was later replaced with the Emergency Alert system in 1997.

    Thanks for reading
    Last edited by Tankman; 26-08-2011 at 09:33 PM.
    Nuclear Bunker & Fallout Shelter Cleaning Specialist. One Mushroom Cloud will keep your bunker, radiant and shiney for years! Ring us now for specialist advice

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