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A 2/3 inch Low-capacity Diode-Gun Plumbicon image pickup tube.
A deceptively simple looking device, some 4 inches long and distantly
related to the humble vidicon (and indeed the radio tube or valve), these were once one of the best imaging devices available. |
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Buried precisely within the optical system of the HL79D camera were
three of these tubes (to pick up the three primary colours). In contrast to current C.C.D. technology, 'tubes' required high voltages, low voltages and much ancillary electronics to make them work. Precision deflection and focusing coils with atendent stable drive circuitry and sensitive, low noise pre-amplifiers, was just for 'starters'. For 'Broadcast Quality' colour, one needed 3 sets of everything, and a very high quality prismatic optical splitter, all perfectly mechanically and electrically adjusted.
For fun in about 1997, I tracked down a manufacturer of these tubes and
enquired as to the cost of a new set. The reply went something like, 'well I suppose we are talking of about £2,000 per tube these days'... They were kind enough though to send me this display sample (probably working) and some technical literature on image tubes. |
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The Plumbicon Image Pick-Up Tube
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