HP-55 Programmable Handheld Scientific Calculator

It dislays 2 digits each for hours, minutes and seconds in the center of the display with 2 more all the way on the right side for tens and hundreds

Hewlett Packard HP-55 Programmable Calculator with Quartz Crystal Timer

Category:Programmable calculators - Wikimedia Commons

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Electronic Calculators—Handheld

HP 55 - 55 steps of programmable memory. Volatile memory meant re-entering programs after shut down. No IN…

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3 Best HP Scientific Calculators for 2019

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