Re: VHF or UHF?
The PL259 connector that my catalogue says is only suitable for use up to about 200MHz due to its non-constant impedance characteristics, is sometimes still referred to by its original name of "UHF connector". Presumably when it was designed, this upper frequency was considered to be UHF.
According to the 1956 edition of the "ITT Reference Data for Radio Engineers", standardisation of frequency band designation seems to have been first agreed at the Atlantic City Radio Convention of 1947, although the CCIR later recommended that the use of such arbitrary names be discontinued. In my days with Plessey in the 1970's the 225-400 MHz band was referred to as the Military UHF band, although it spans the Atlantic City VHF and UHF bands.
I guess the terminology has changed as the art has developed. In my late father's 1933 edition of Scott-Taggart's "Manual of Modern Radio", what we would now call "Radio Frequency [RF], is called "High Frequency" [HF]. German still retains this pre-war usage, as the German word for "Radio Frequency" is "Hochfrequenz", literally, "High Frequency", often abbreviated as "HF". Before I retired my work often involved scrutinizing German technical documents or their English translations. Often the English translator was evidently not aware that HF = RF, which sometimes caused confusion.
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