The Monroe Calculator Models K, KA, and L

The Monroe Calculator is a mechanical calculator that began production from 1914, but only became successful with the introduction of the model K in 1921. Model L followed in 1929, and variants remained in production till the 1960s. In this video I demonstrate the model K, and model L, as well as the electrically driven model KA. Video of an older model, the model F:    • The model F Monroe Calculator   For more information on the Monroe Calculator, as well as the other mechanical calculators in my collection, visit my website: https://www.jaapsch.net/mechcalc/ 0:00 Introduction, History 1:05 Model K 1:29 Addition 2:13 Clearing 2:46 Subtraction 3:38 Multiplication 5:13 Counter 6:32 Item Count 9:00 Mechanism 12:46 Model L 13:35 Serial number 13:53 Model designations 15:13 Model L Item Count 15:42 Model KA 16:20 Crank 16:39 Model KA comparison 17:11 Bell 18:35 Model KA add subtract 18:57 Decimal markers 19:55 Outro