Thursday, June 26, 2014

The Screwtape Fascimilie Broadcasts

Note the variation on the Quick Brown Fox line above. That exact sentence was the first message sent on the Moscow–Washington hotline in 1963. It was sent by "secure" fax over land line, two decades after the death of facsimile broadcasts. More here.

It was imagined in the 1930s as a tool to communicate stock quotations, a news service, aircraft communications and as a home news service. I debate whether this was a gamble a farce or charity. R.C.A. invested a huge amount of money, time, and research into this technology in the middle of the great depression— an era when it was least likely to succeed commercially. It eventually produced a functional system which while commercially unfeasible, at least produced patentable technology that was later used in early television.

The technology of image transmission begins with Alexander Bain in 1842.  It was almost another 100 years before they got even close to a commercial service. In 1935 RCA was performing long-distance tests of facsimile transmissions up to 375 miles out from their transmitter in Rocky Point, NY (Long Island.) Yes that's approximately from New Haven, CT to Pittsburgh, PA. the AM transmissions worked best in the daytime due to multi-path interference effecting their signal on 38.6 Mc/s.  Portable receivers were installed in an automobile for continuous mobile testing. 

In 1936 the moved onto courting the airlines. A test was set up with 6 sets of receiving equipment for American Airlines hubs in Newark and Chicago. A 1Kw transmitter w2as set up on 10190 kc but testing ended after only 2 weeks because of interference from another unnamed station on the same frequency. The system was tested again with Western Airlines in Chicago and Kansas City on 2710, 4110, 6510 and 8015 kc. Tests again had difficulty with multi-path, and ignition noise. A further test in 1936 with Eastern Airlines in Miami and Atlanta was plagued by echo effects.

Enter the government. The Bureau of Air Commerce (established 1934) was excited about the idea and wanted to transmit weather reports on UHF between all airports.  Test equipment was installed in Maryland at Silver Hill and Sparrows Point on 61 and 65 mc. It was somewhat more of a success. The equipment was moved to Reading and Harrisburg for a test on 1674 kc and 190 kc in use by the state police. 

Later test tried to send weather maps to ships at sea, transmit newspapers to homes and even less plausible schemes. In the end it proved to be a solution looking for a problem.  The Bureau of Air Commerce was split into the Civil Aeronautics Administration (CAA) and the Civil Aeronautics Board (CAB) which collectively lost interest. RCA saw quickly that television was the future and wisely changed strategy.

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