The Itron DP89A is an early transitional multi-digit VFD, one which straddles the line between first generation single digit display tubes and the modern flat glass VFDs that would soon come to dominate the vacuum fluorescent display market. The DP89A is constructed using a primitive 'bathtub' style package, with the display elements mounted to a metal bathtub which has a glass lid sealed to its upper surface with frit. This glass lid has a black plastic mask attached, which hides most of the internal construction of the display. Two 14 pin DIP connectors provide communication with the outside world, and an evacuation nipple is located on the lower edge of the display package. Unfortunately the large bathtub package prevents the display from being tiled horizontally or vertically; the DP89A was likely purpose built by Itron for the 1970's calculator industry where tiling would not be required. The DP89A was used in a number of early calculators produced by Rockwell, and is believed to have been released in 1974.
Electronics engineers were not long in realizing the virtues of multi-digit VFDs, and metal bathtub displays like the DP89A were quickly replaced by all glass flatpack VFDs which flooded the consumer market. Glass flatpack VFD displays are still produced today, and still see heavy use in appliances and industrial electronics.
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