The Brunsviga D 13Z/1 double calculator

[@villeelomaa7836]

Thanks for this video, Jaap. I had never before understood the idea of these double calculators. This calculator must have been extremely expensive, when it was new.

[@BassistInATutu]

Hi! That's really cool. I just got a 13z which, after very little cleanup, is working really nicely. Love these early machines. Thanks for all the great videos! :)

[@heikkileivo]

Brilliant, what a gem! Never thought a mechanical vector machine could exist.

[@robertlozyniak3661]

Of course, you need a table of sines and cosines to go along with it. Unless you want to grind out the Taylor series by hand, or something of that sort.

[@ruuddekorte4541]

Wat ontzettend leuk om " de bronstig" zoals hij bij de cartografische dienst in Rotterdam werd genoemd in werking te zien! Dankjewel voor de uitleg.

[@Hertog_von_Berkshire]

These machines were known as "coffee grinders" in the British Army. They were chiefly used by the Royal Artillery and the Royal Engineers. Many of them were lost during the retreat to Dunkirk in 1940. Throughout WWII and for some 10 years thereafter, the British Army used Twin Marchant machines, each comprising two American made Marchant units co-mounted in the UK into a double arrangement, mimicking the D 13Z. by all accounts, the Twin Marchant never worked as smoothly as the Brunsviga.

[@jaapsch2]

There were also twin Brittanic machines. Alan Turing used one, which you can see on Cris Vande Velde's site here: www.crisvandevel.de/sttu.htm

[@Hertog_von_Berkshire]

The twin Brittanic is generally regarded as a failed experiment. I believe they were made in very small numbers. Alan Turing's may well be the only one. The Twin Marchant was was commissioned when the Brittanic approach was deemed to have failed.

[@Persilya]

Thank you very much for this video 😮😊

[@alanesq1]

Hi. I have just been given a single Brunsviga which I suspect used to be the right side of one of these. It has no lever on the left side and it looks like a shaft has been cut off (more like snapped off).

[@someonespadre]

I learned something today…put the starting coordinate (we always start at a non-zero coordinate) into the correct place in the lower register then multiply sine by distance…it calculates the latitude or departure and adds it to the last coordinate. Pretty cool. Although I usually want the latitudes and departures for calculating area. If the next course is negative then wind it backwards.

[@someonespadre]

Enter cosine in the left and sine in the right then turn up the distance in both. Latitude in the left and departure in right. We use Y-X order. Later could add up the coordinates in one operation. We also use quadrant bearings over here so cosine is always delta Y and sine is delta Z.

[@someonespadre]

We call your first direction North 40° East (the opposite direction being South 40° West), latitude +, departure+. Your second bearing is North 65° West (the opposite direction is South 65° East), latitude +, departure -.

[@ChrisStaecker]

Crazy machine- how heavy is it? Also the registers at the bottom can go negative, right? (I assume they don't roll back to 999999.) Is there a bell? Thanks for the video as always!

[@jaapsch2]

I'm not sure how heavy it is. The D13Z/2 weighs 15.5 kg, so this one weighs one counter register less than that. That carrying handle on the right really cuts into your fingers. Unfortunately the registers roll back to 9999..9 when they underflow, so there is no handling of negative numbers like there is in the counter register of these Brunsviga machines. And yes, a bell rings when that happens. I think there is only one warning bell that is used for both registers.

[@GrumpyTim]

Hi Jaap, that's so exciting to see exactly what one of these double machines was used for, excellent demonstration, thanks for showing it. If I had one of those I'd have to set myself lots of coordinate calculation challenges, or get someone else to set the challenges for me.

[@rubberswan]

A very nice machine! I have the very similar D13ZK, but I’m struggling to see the difference between yours and mine. I much appreciate the Co-ordinate calculation demo.

[@jaapsch2]

On the standalone machines the K indicates that it has that switch for combined clearing of input and counter. I think that switch was introduced on these double/triple machines, and later also transferred to the single machines, and only at that point did the double machines get the K in the model name as well. So for double/triple machines there is no difference.

[@robertlozyniak3661]

I notice that the switch in the middle is marked with Roman numerals I through IV. What do those signify?

[@jaapsch2]

To be honest, I don't know. Most of the others I've seen pictures of just have a pair of arrows at each end, either pointing in the same direction or in opposite directions to signify that the drive shafts of the machines go in the same or in opposite directions. The markings on this one are baffling, especially since on both sides the arrows point in opposite directions. The various registers are usually denoted by roman numerals, but that is a bit odd here since it only has one counter register. I have not gone through the complicated manual in detail, as that would take much more time and effort than I want to spend, but these Roman numerals are used a lot in there.

[@jaapsch2]

I now think that the Roman numerals represent the four quadrants of the plane. After setting the switch appropriately, the arrow there shows which way you have to turn the crank.

[@JCEurovisionFan1996]

Could you do a .pdf of that manual?

[@jaapsch2]

It's on my todo list.

[@jaapsch2]

It has now been scanned and is available from my site: www.jaapsch.net/mechcalc/brunsviga.htm#myd13z1 and from archive . org: archive.org/details/geodaetischesrechnen

[@nmmm2000]

If standard mechanical calculator is a CPU (a computer processor), then this Brunswiga machine shoul be a GPU (a graphic card) 😂😂😂

[@shko0729]

どっぺる