Jaap ScherphuisThe EOS calculator is identical to the Hannovera CK calculator. It uses an oscillating segment system somewhat similar to the Demos, but whereas the Demos uses complementary digits for subtraction, the EOS allows you to simply turn the crank in the opposite direction like a pinwheel machine. About 1000 were produced, and sold in Switzerland.
The mechanism of the EOS mechanical calculatorJaap Scherphuis2021-05-08 | The EOS calculator is identical to the Hannovera CK calculator. It uses an oscillating segment system somewhat similar to the Demos, but whereas the Demos uses complementary digits for subtraction, the EOS allows you to simply turn the crank in the opposite direction like a pinwheel machine. About 1000 were produced, and sold in Switzerland.
For more information on this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:39 Addition cycle 3:28 Subtraction cycle 5:11 Oscillating mechanism 5:40 Counter mechanism 7:07 Automatic input clearing 7:52 Clearing output register 8:17 Cam wheels 9:24 Outro26-sided antique stone dieJaap Scherphuis2022-11-19 | This antique gaming die was made in Zöblitz from the locally mined serpentine stone, probably between 1880 and 1910. It is a rhombicuboctahedron, so it has 26 sides. Only the 18 square sides are used. Twelve sides have the numbers 1 to 12, and six sides have letters. Two games are played simultaneously. The letters are for Put & Take, a game that goes back to the middle ages.
0:00 Introduction 0:52 History 1:46 Instructions 8:39 Serpentine 9:37 Carving 10:21 OutroThe AEG KAL portable ticket machineJaap Scherphuis2022-11-04 | This AEG KAL ticket machine was used by the Dutch national railways in the 1970s. The ticket details are set with the input pins, and a turn of the crank then issues a newly printed ticket. It has a locked cartridge with a control copy of all tickets printed.
For more information on this and other machines in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:23 Input 1:13 Printing a ticket 2:07 Removing from the stand 2:29 Counter registers 3:33 Opening the case 4:05 Control cartridge 6:24 Ink roller 6:53 Setting the date 7:15 Print locking mechanism 8:04 Print cycle 9:20 OutroThe Olivetti Summa 15 adding machineJaap Scherphuis2022-10-22 | The Olivetti Summa 15 adding machine was made in Italy in the 1950s. Its most unusual feature is the multi-function button that looks like a joystick.
For more information on this and other machines in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction, history 1:06 Manual lever 1:36 Paper feed 1:53 Multi-function button 2:30 Entering numbers, clearing input 2:57 Addition 3:15 Totals and subtotals 4:05 Subtraction 4:25 Non-Add function 4:49 Button release 5:08 Repeat, multiplication 6:28 Ink ribbon 7:05 Negative totals 7:42 Serial number 8:11 OutroPrecisa 102-1 adding machineJaap Scherphuis2022-10-08 | The Precisa 102-1 adding machine was made in Switzerland in the early 1950s. It has some quirks that you need to be aware of when using it, and its recall functionality is very unusual.
For more information on this machine and others in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:51 Addition 1:16 Totals and subtotals 1:58 Subtraction 2:25 Negative totals 3:30 Non-add 3:55 Non-print 4:29 Repeat, multiplication 5:34 Recall 8:17 Crossbow logo 8:50 Opening the case 10:25 Printing mechanism 11:01 Subtraction mechanism 11:53 Non-print mechanism 12:40 Reassembling case 13:08 OutroThe Addo-X 341 adding machineJaap Scherphuis2022-09-25 | The Addo-X 341 is an adding machine made in Sweden in the 1950s. My version has a carriage for feeding paper sheets, but most just had a simple paper roll.
For more information on this and other machines in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:25 History 1:35 Entering numbers 2:00 Addition 2:16 Subtraction 2:50 Subtotals and totals 4:20 Symmetric keyboard 4:45 Multiplication 5:55 Step-O-Matic 6:54 Non-Add 7:14 Carriage 8:44 Addo-X 351 9:33 Ink ribbon 9:49 Power cord 11:06 OutroThe Olympia AE-8 adding machineJaap Scherphuis2022-08-30 | The Olympia AE-8 is an adding machine from 1967. It is fairly unremarkable, with a standard keyboard and controls.
For more information about this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:51 Addition 1:17 Total/Subtotal 2:05 Subtraction 2:39 Negative totals 3:09 Non-add 3:29 Clearing 3:38 Repetition/Multiplication 5:02 Ink ribbon 5:47 Opening case 7:30 Power cord 8:34 Inserting paper 9:26 Mechanism in action 10:59 OutroThe Summira S printing adding machineJaap Scherphuis2022-08-05 | The Summira S is a version of the Summira 7 adding machine but with a printer mechanism at the back. Pulling the large handle will cause the current input to be printed, either in black or in red depending on whether subtraction mode is selected.
For more information about this and other calculating machines in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:19 Addition 1:02 Clearing 1:32 Multiplication 2:23 Subtraction 3:28 Printing 6:20 Printing mechanism 8:06 History 8:34 OutroBeaver adding machineJaap Scherphuis2022-07-15 | The Beaver is a very rare adding machine that was made in Japan in 1964. It was exported and sold by Ito-Ya Ltd., a stationery supplies company.
For more information on this and other calculating machines in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:28 History 1:44 Addition 2:42 Subtraction 4:25 Clearing 4:48 Complementary numbers 5:48 Opening case 8:35 Mechanism 11:02 OutroThe SCM 1011 CB adding machineJaap Scherphuis2022-07-01 | The Smith-Corona-Marchant 1011CB adding machine has a very distinctive styling in orange and brown.
For more information about this machine and others in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction, History 0:45 Addition 2:10 Clearing input, Non-add 2:51 Subtraction 3:55 Repeat, Multiplication 5:00 More history 5:59 Opening the case 7:29 Paper roll 7:55 OutroThe Precise adding machineJaap Scherphuis2022-06-18 | The Precise adding machine is a simple co-axial adder with a built-in stylus. It was made between 1946 and 1950 in Chicago, and despite its short production period it has a rather complicated history.
For more information about this and other calculating machines in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:27 Addition 0:54 Clearing 1:22 History 1:41 Precise Developments Co. 2:54 E.C.A. 5:25 Tastee-Freez 7:01 OutroThe Multo mechanical calculatorJaap Scherphuis2022-06-03 | The Multo calculator was made in Sweden from 1949 till 1966. It is a model 3, so it has an input display but no back transfer.
For more information on this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:30 History 1:01 Nice touches 1:38 Addition 1:48 Counter 2:24 Multiplication 3:06 Clearing 4:00 Seizing up 6:17 Further history 7:22 OutroThe Everest Plurima Manuale adding machineJaap Scherphuis2022-05-20 | This adding-listing machine was made by Serio in Italy from about 1960 till 1965. It is manually driven, and handles subtraction and negative totals.
For more information about this machine and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:20 Input 0:40 Addition 0:55 (Sub)total 1:59 Non-add 2:24 Subtraction 2:50 Negative totals 3:31 Multiplication 4:50 Ink ribbon 6:20 Opening case 7:05 OutroThe Brunsviga 11S mechanism in actionJaap Scherphuis2022-05-10 | This shows the Brunsviga 11S mechanical calculator without its case, calculating 355 divided by 113.
For more information on this and the other calculators in my collection, please visit my website: jaapsch.net/mechcalcThe Brunsviga 11S mechanical calculatorJaap Scherphuis2022-05-06 | The Brunsviga 11S is an electrically driven mechanical calculator. It is similar to the Brunsviga 11E but with a full keyboard instead of input pins. It has automatic division.
For more information about this machine and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:21 History 1:32 Addition 2:13 Subtraction 2:30 Clearing 3:04 Multiplication 4:52 Division 6:20 OutroThe Everest Z5R calculatorJaap Scherphuis2022-04-22 | The Everest Z5R is a mechanical calculator made in Italy in the 1950s. It was made by S.A. Serio in Crema. The design is generally similar to the Facit TK, so it uses a pinwheel mechanism, has a 10-key keyboard, and an internal carriage.
For more information on this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:17 Inputting numbers 0:43 Addition 0:55 Multiplication 1:37 Subtraction 1:47 Shortcut multiplication 2:19 Clearing 2:37 Counter direction 3:45 Division 6:47 Back Transfer 8:43 History 10:24 OutroThe Summira 7 adding machineJaap Scherphuis2022-04-09 | The Summira 7 is a small adding machine. It can do direct subtraction, and was made in West Germany from about 1955 to the mid 1970s. It is very similar to the Resulta.
For more information on this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:18 Addition 1:07 Clearing 1:55 Small multiplications 2:33 Subtraction 3:53 History 4:42 OutroOtis Kings Pocket CalculatorJaap Scherphuis2022-03-25 | Otis King's Pocket Calculator is a cylindrical slide rule. It was made from about 1922 till the early 1970s. This is a model K from the early 1960, which has just two logarithmic scales which allow you to multiply or divide.
For more information about this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:31 Description 2:09 Multiplication, Division 5:18 Otis King 6:04 Carbic Limited 7:32 OutroThe Countess adding machineJaap Scherphuis2022-03-11 | The Countess adding machine is a very simple adding machine for British currency. It only does addition, not subtraction. It was made by Summira in Germany in the 1960s or early 1970s.
For more information on this and other machines in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:14 Columns for currency 1:11 Clearing 1:45 History 2:50 Opening the case 3:38 Carry mechanism 5:48 OutroThe Russian Felix M calculatorJaap Scherphuis2022-02-25 | The Felix M is a pinwheel calculator made in Russia from 1929 till 1978 with virtually no change in its design. It is closely modelled on the pinwheel calculator made by Odhner in St. Petersburg before the Russian revolution, because Odhner's machinery was confiscated and used to set up production of the Felix. Millions of these calculators were made.
Errata: The first Felix was probably made in 1929, not 1928, and my Felix-M was probably made in 1976, not 1975.
For more information about this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:44 The design, addition 1:05 Clearing registers 1:57 Counter, subtraction 2:42 Input clearing 3:11 Reversing direction 4:10 History 5:28 Felix Dzerzhinsky 8:08 OutroThe Precisa 364 adding machineJaap Scherphuis2022-02-15 | The Precisa 364 is an adding listing machine that can also do multiplication. It was made from 1963 to 1978. The Precisa 160 is the same but without the multiplication functionality.
For more information about this and other machines in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction, Precisa 160 0:41 Precisa 364 1:42 Addition 2:15 Subtotal 2:46 Total 3:10 Subtraction 4:11 Non-add 4:45 Repeated addition 5:04 Clearing input 5:15 Repeated subtraction 6:14 Multiplication 7:08 Negative multiplication 7:36 Squaring 8:21 Shortcut multiplication 9:00 Repeated multiplication 10:45 Opening case 12:10 OutroThe Hasbro Adding MachineJaap Scherphuis2022-02-03 | This is a toy adding machine made by Hasbro in about 1961. It is similar to the Wolverine, but plastic instead of metal.
For more information on this and other machines in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:19 Unboxing 0:44 Description 1:10 Addition 2:00 Totals bar 2:25 Clearing 3:35 Mechanism 6:19 Patents 6:49 OutroThe American Adding MachineJaap Scherphuis2022-01-26 | The American Adding Machine was made from about 1913 till 1922 by the American Can Company, and for a short while after that by The American Adding Machine Company. The one I show here is the earliest model, which has a gorgeously patterned case.
For more information on this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction, History 0:54 Input mechanism 1:32 Addition 2:15 Clearing 2:55 History 5:22 OutroThe first and the last Sumlock calculator modelsJaap Scherphuis2022-01-15 | The Sumlock was made by Bell Punch in the UK from 1940 till the late 60s. It is used exactly like the Comptometer. Here is the first model (1940-1945, made by subsidiary London Computator Corporation) and the last model (1953-1970).
Errata: There are of course 20 shillings in a pound, not 19.
For more information about this machine and others in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:22 British currency 1:22 Error detection 2:47 Model 913!? 4:22 Model F or SF 4:55 Error on new model 6:00 OutroThe Sumlock mechanical calculator, and some advanced calculation techniques.Jaap Scherphuis2022-01-08 | The Sumlock was made by Bell Punch in the UK from 1940 till the late 60s, but these two were made in the early 1950s. They are used exactly like the Comptometer. After a short demo, I show how to multiply the register result by another number, and explain division in a bit more detail.
For more information about this machine and others in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:26 History 0:59 Overshoot prevention 1:40 Error detection 2:31 Models 2:58 Multiplication 4:59 Division 9:50 OutroThe Mercedes Euklid 16 mechanical calculatorJaap Scherphuis2021-12-29 | The Mercedes Euklid 16 is a mechanical calculator that was in production from 1927 till about 1935. The Euklid machines use a unique proportional lever mechanism. This model was the first to use a modular keyboard with tightly packed cubical keytops. It can do automatic division, and has a neat automatic decimal point system for multiplication.
For more information on this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:21 Keyboard 1:00 Crank 1:31 Addition 2:30 Subtraction 3:12 Clearing 3:29 Multiplication 4:48 Decimal points 6:35 Automatic division 9:05 Serial number 9:44 OutroThe Victor 16-83-54 Adding MachineJaap Scherphuis2021-12-18 | The Victor 16-83-54 Adding Machine was made from 1960 till about 1967. It is very similar to the series 6, with a full keyboard, except that some of the controls have moved and are now buttons on the keyboard. This version has an electric motor. I forgot to show subtraction in this video, but that is the same as addition except that you press the minus button.
For more information about this and other calculators in my collection, please visit my website: jaapsch.net/mechcalcA short history of the ComptometerJaap Scherphuis2021-12-04 | I gave a 10 minute talk at the Gathering for Gardner 12 conference in 2016:
"Before electronic computers and calculators, there were mechanical calculating machines. The Comptometer was one of the most widely used calculating machines, used all around the world for almost 80 years. It quietly changed the world, yet is almost forgotten today."
This video was a practice run I made to see if I got the timing about right. The actual talk was filmed, and can be found here: youtube.com/watch?v=Q2G-383ij8A
For more information about the Comptometer and the other mechanical calculators in my collection, visit my site: jaapsch.net/mechcalcThe Elm City CounterJaap Scherphuis2021-11-20 | The Elm City Counter is a simple counter, mostly used in the printing and textile industries. It was first made in the early 1880s, but ones like this one that have "C. J. Root Co." on the front were made after 1907. In 1928 the company merged with Veeder to become Veeder-Root, and the inscription of the Elm City Counters were changed appropriately. Production continued at least through the 1930s.
For more information on this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction, History 3:05 Description 6:01 C. J. Root 8:00 Mechanism 10:06 OutroThe Sirius adderJaap Scherphuis2021-10-31 | The Sirius adder was made Master, who also made the Master and the Business adders. This one has attachments for use in multiplication and even division, but these are completely unusable. The box contains not only instruction manuals, but also various ads, including rather oddly an ad for the Sirius itself.
For more information on this and other machines in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:53 Addition 1:33 Carry operation 2:14 Clearing 2:39 Scriptor attachments 6:52 Testimonials 7:22 Sirius ad 7:45 Guarantee 8:24 Scriptor instructions 8:52 Special offer 9:32 Instruction booklets 10:54 Ad for Electric Master 11:35 Receipt 12:04 Packing up 13:14 OutroThe Triumphator CRN2 pinwheel mechanical calculatorJaap Scherphuis2021-10-08 | The Triumphator CRN2 mechanical calculator is a rather large pinwheel machine. It was in production in Leipzig, East Germany, from 1959 till about 1965.
For more information on this and other calculators in my collection, please visit my website: jaapsch.net/mechcalcThe Multifix E1R mechanical calculatorJaap Scherphuis2021-09-24 | The Multifix E1R mechanical calculatorThe Brunsviga D 13Z/1 double calculatorJaap Scherphuis2021-09-17 | The Brunsviga D 13Z/1 consists of two calculators, side by side, connected to a single crank. Double calculators like this were used for calculations involving coordinates, such as land surveying, and were also often used by the military. I give a simple example of such a calculation.
For more information about this and other calculators in my collection, please visit my website: http://www.jaapsch.net/mechcalc
0:00 Introduction 1:14 Uses for double calculators 2:50 Description of the calculation, part 1 3:36 Doing the calculation, part 1 5:24 Description of the calculation, part 2 6:19 Clearing counter and input registers 7:07 Doing the calculation, part 2 9:43 Clearing the output registers 9:56 Manually setting the output registers 10:28 OutroThe Denominator, a pay roll adding machineJaap Scherphuis2021-09-10 | The Denominator is a rare adding machine that simply contains a separate counter for each denomination of US currency. You would go through a stack of pay slips, entering the coins and bills needed for each one, so that at the end you'd know how many coins and bills to take out from the bank to pay your staff. The Denominator Adding Machine Company was founded in 1914 by Frank H. Morse to make this machine. The company still exists today, now called the Denominator Company, and is still making mechanical counters.
For more information an this and other machines in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:24 What it is used for 0:54 Company history 3:21 How to operate it 3:45 Serial number 4:08 Production 4:39 Opening the machine 6:22 Mechanism 7:55 Repairs 9:23 OutroRare Lipsia Addi 7 adding machine with printing mechanismJaap Scherphuis2021-09-03 | The Lipsia Addi 7 was released in 1930, but this variant with a printing mechanism was not success and is therefore quite rare. After the second world war Lipsia was merged with Triumphator, and the Addi 7 was given a makeover and released as the Triumphator KA.
For more information on this and other calculators in my collection, please visit my website: jaapsch.net/mechcalcThe Precisa 117 mechanical calculatorJaap Scherphuis2021-08-29 | The Precisa 117 is a pinwheel calculator with a 10-key keyboard, clearly inspired by the Facit calculators. Its main register and counter are stationary while the input register is on a moving carriage. It was made from 1952 until about 1963.
0:00 Introduction 0:33 Addition 1:35 Clearing 2:15 Subtraction 2:28 Multiply 3:17 Division 5:16 Precisa history 6:44 Serial number 7:02 OutroA steam engine revolution counterJaap Scherphuis2021-08-14 | This antique revolution counter was very likely used with a steam engine, and probably made in Germany in the 1880s or 1890s. It has an unusual eccentric gear mechanism to drive the units wheel, and is one of the first counters to use the carry mechanism that is in use in almost all odometers made today.
Further research leads me to believe that this counter was made by Schäffer & Budenberg in Buckau.
For more information on this and the mechanical calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:48 Carry mechanism 1:12 Eccentric gear drive 1:57 Reset mechanism 2:23 History - Eduard Stalmann, Buckau 3:46 OutroThe Facit CA1-13 fully automatic mechanical calculatorJaap Scherphuis2021-08-06 | The Facit CA1-13 is a fully automatic electromechanical calculator. Facit made their first fully automatic calculator in 1945, and that evolved into this model which appeared in 1956 and was produced until the early 1970s. As well as the three visible registers it has an internal register used to store the first factor in a multiplication.
I apologise for the wandering focus of my camera.
For more information on this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:37 Addition 1:08 Clearing 1:28 Semi-automatic multiplication 3:06 Subtraction 4:24 Automatic carriage shift 5:38 Automatic multiplication 8:14 Division 9:52 Aborting division 12:09 The NEG button 13:03 OutroThe Sterling Dial-A-Matic adding machine, 6-dial modelJaap Scherphuis2021-07-30 | This Sterling Dial-A-Matic adding machine is a simple rotary adder with six dials and a clearing lever. It was first produced in the mid 1950s.
0:00 Introduction 0:10 The box 0:58 Models 1:19 Stylus 1:37 Addition 2:14 Clearing 4:08 Subtraction 5:05 OutroThe Schubert DRV mechanical calculatorJaap Scherphuis2021-07-23 | The Schubert DRV is a very well-designed pinwheel calculator. It was in production from 1952 till the 1970s. The controls are set up so that they can be used with one hand, and designed to need minimal effort. It was designed by Emil Schubert, who had previously co-founded and run Thales.
For more information on this calculator and other machines in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:20 Addition 0:46 Multiplication, shifting the carriage 2:11 Clearing 4:34 Back Transfer 5:25 Serial number 5:59 History, Emil Schubert 8:03 Models 9:29 OutroThe Ken+Add adding machineJaap Scherphuis2021-07-16 | The Ken+Add is a small dial adder, built into a nice metal case that also contains the stylus. It was named after its designer, Kenneth Pangburn, and made from 1950 until about 1958 or so. It used to have a "Magic Slate" inside the lid of the box, which was a waxy rubbery backing with a plastic semi-transparent film laid on top that you could draw on with the stylus. Peeling up the plastic sheet would erase the drawing.
For more information on this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:32 Addition 1:30 Subtraction 1:55 Clearing 2:26 History 3:20 Magic Slate 4:15 Patents 4:40 Similar machines 5:09 OutroThe Antares P4 mechanical calculatorJaap Scherphuis2021-07-09 | The Antares P4 is a pinwheel calculator made by the Italian company Organizzazione Pozzi in the 1950s.
For more information on this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 History 0:20 Models 1:55 Addition 2:11 Counter 2:35 Clearing 3:09 Serial number 3:45 Colours 4:15 Further history 4:58 OutroHow the Original Odhner pinwheel calculator worksJaap Scherphuis2021-07-03 | I'll show and describe how an Odhner pinwheel calculator works. It is an Original Odhner model 24.
For more information about this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:29 Pinwheel 1:14 Carry mechanism 3:27 Latch 4:26 Input clearing mechanism 7:00 Counter increment mechanism 10:45 Counter carry mechanism 13:34 Back transfer mechanism 15:20 Input display mechanism 16:02 OutroThe Original-Odhner 24 mechanical calculatorJaap Scherphuis2021-07-03 | The Original-Odhner model 24 is a mechanical calculator with a pinwheel mechanism. It has a large capacity of 20 digits, and a back transfer mechanism. It was made in Göteborg in Sweden from 1940 (or maybe a bit earlier) until about 1948.
In 1875 Willgodt Odhner made the pinwheel calculator that was the ancestor of almost all pinwheel machines that came after it. He died in 1905, after which his sons took over his calculator production business. It was they who moved to Sweden when the business was taken over after the Russian revolution (NOTE: In the video erroneously imply that Willgodt moved to Sweden).
For more information on this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:19 History 2:10 Addition 2:42 Subtraction 2:57 Clearing register and counter 3:07 Multiplication 4:17 Clearing input 5:25 Counter 6:13 Division 8:02 Main carry mechanism 9:27 Counter carry mechanism 10:13 Back transfer mechanism 11:36 OutroThe Calculator adding machineJaap Scherphuis2021-06-18 | The Calculator adding machine was made between 1915 and 1922, at which point it was replaced by the Lightning Calculator. It is almost identical to the Bonham & Schram calculator from 1905.
For more information on this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 History 1:02 Stand and stylus 1:18 How to use 2:50 Stand and stylus 3:35 Further history 4:02 OutroThe SIMEX Caroline adding machineJaap Scherphuis2021-06-11 | The Caroline is a simple adding machine originally made by Simex. The one shown here is the more common French licenced copy. It was made in the 1960s. It's mechanism is very similar to the Addipresto/Addimat.
For more information on this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 History 1:15 How to use 1:56 Carry mechanism 2:16 Clearing 2:34 History 3:22 Mechanism 6:13 OutroThe Melitta VII/16 pinwheel calculatorJaap Scherphuis2021-06-04 | The Melitta VII/16 is a mechanical calculator with a pinwheel mechanism, which was made in East Germany from 1955 till at least 1963. It has a unique input mechanism with input pins that remain stationary when you turn the crank.
For more information on this and other calculators in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:18 Input mechanism 1:34 Addition, multiplication 2:48 History 6:41 Clearing 7:30 Division 9:54 Back transfer 11:44 Carriage release 12:30 OutroThe Madas Portable 12e mechanical calculatorJaap Scherphuis2021-05-30 | The Madas Portable 12e is a mechanical calculator made by H. W. Egli in Switzerland from 1931. Versions of this machine were made until the late 1960s. This is the simplest electric model, and most later machines were much more automated. Even though this model is electric, shifting the carriage is still done manually. For this reason it has no fully automatic division
For more information on this and other machines in my collection, please visit my website: jaapsch.net/mechcalc
0:00 History 1:50 Addition 2:24 Subtraction 2:42 Clearing 2:49 Multiplication 4:32 Division 6:53 Manual crank 7:32 Removing carriage 8:08 Serial number 8:34 OutroThe Madas BZS mechanical calculatorJaap Scherphuis2021-05-22 | The Madas BZS is a mechanical calculator made by H. W. Egli in Switzerland. The first version of the Madas Portable is from 1931, but this fully automatic one is from about 1960. It has fully automatic division and multiplication. Note however that I have not been able to get the multiplication working, as it seems that some parts deep inside are stuck together and I have not yet dared to take it apart far enough to reach those parts.
For more information on this and other machines in my collection, please visit my website: jaapsch.net/mechcalc
0:00 Introduction 0:16 Addition 0:41 Subtraction 1:03 Semi-automatic multiplication 2:04 Clearing 2:22 Division 3:42 Tabulation 4:55 Aborting division 6:25 Counter direction 7:00 Setting multiplier 8:06 Automatic multiplication 9:12 Carry mechanism 10:24 Split register 11:10 Decimal markers 11:40 OutroThe EOS mechanical calculatorJaap Scherphuis2021-05-08 | The EOS calculator is identical to the Hannovera model CK, but was made for the Swiss market. It uses an oscillating toothed segment mechanism which was easier to manufacture and did not infringe on Brunsviga's patents, unlike Hannovera's previous models which were pinwheel machines. The mechanism is similar to that of the Demos, but better because it can do subtraction by turning the crank in reverse.