Albert's Attic Gallery

1950 advertisements

Here we have three aerial adverts from the May 1950 edition of Practical Television.

Of particular interest is the ‘Visio’ three-element aerial. The addition of one or more director elements drives the characteristic impedance of the driven element downwards, so for a total of four or more elements a folded dipole is de rigueur. Folding the dipole once multiplies the impedance fourfold and thus compensates for the loading of the extra elements. But to fold the dipole twice, for only one director, seems excessive. The word ‘gimmick’ comes to mind. But perhaps the very close element spacing calls for it, or perhaps the aerial included a matching device of some sort. I hope the chimney fixing shown was a figment of the artist’s imagination rather than an accurate depiction.

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