Re: 405-Line VHF Aerials in 2013
re #35, contemporary trade leaflets indicate that the Antiference Antex was introduced in 1949. An Antiference leaflet refers to it having been in use for 2 years before the 1951 Festival of Britain, and a provisional patent application was also filed in 1949.
The Dublex may have been designed to get around the Antiference Patents. The (undated, probably circa 1952) Aerialite leaflet says that a patent was applied for the Dublex design. While Aerialite did have three patents granted around 1950, none relate to the Dublex configuration. At that time, only patents that were accepted were published, so possibly their application relating to the Dublex was abandoned or refused. I have another Aerialite leaflet, also undated, that mentions a "Unex X-shaped aerial", as well as the Dublex X-shaped : no illustration unfortunately, but the Unex was less sensitive (50 miles) that the Dublex (65 miles).
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