# Forgotten analog technology **URL:** \ **Category:** In My Humble Opinion\ **Created:** [December 28, 2007, 2:47am UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433 "2007-12-28T02:47:14Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![cornflakes](https://avatars.discourse-cdn.com/v4/letter/c/9d8465/32.png) [@cornflakes](https://boards.straightdope.com/u/cornflakes)\ **Post date:** [December 29, 2007, 5:11am UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/21 "2007-12-29T05:11:47Z")
[QUOTE=beowulff] You’re not thinking of an _Interferometer_, are you? [/QUOTE] No, I’m thinking of ASML’s [through the lens (TTL)](http://www.freepatentsonline.com/6914664-0-large.jpg) alignment system. A set of gratings are passed under the lens. Laser light is scattered off of the marks, and the first order light is passed through a similar set of marks on the reticle. What passes through is sampled and the point where the 8um and 8.8um gratings transition at the same place is considered the alignment point. That’s the simple description. The concept is still more or less used in their latest alignment systems, but I’m not sure of the details. Wafer stages have used interferometry since the '70s, scanner stages since the early '70s. Interferometry is more accruate for measuring relative movement, but it doesn’t provide an absolute reference point. ---
**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\ **Post date:** [December 29, 2007, 5:12am UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/22 "2007-12-29T05:12:49Z")
**Max Torque** , I had two of those, back in the '70s. I actually wore out the first one, and had to replace it. I got to be really fast on it too. ---
**Author:** ![Tuckerfan](https://avatars.discourse-cdn.com/v4/letter/t/eada6e/32.png) [@Tuckerfan](https://boards.straightdope.com/u/Tuckerfan)\ **Post date:** [December 29, 2007, 2:41pm UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/23 "2007-12-29T14:41:21Z")
[QUOTE=cornflakes] Verniers are a pretty accurate way of measuring distance. They’re used in making semiconductors and can hold alignment down to a repeatability of a few nanometers or less (The actual measuring is done through digital sampling of laser light that has been relected and scattered by the vernier.) It may be easier to quantify things through digital methods but the world as we experience it is still analog. [/QUOTE] Vernier calipers are also less prone to error than dial or digital calipers. (They’re not as accurate as using a micrometer, either.) ---
**Author:** ![Steve\_Wright](https://avatars.discourse-cdn.com/v4/letter/s/848f3c/32.png) [@Steve\_Wright](https://boards.straightdope.com/u/Steve_Wright)\ **Post date:** [December 29, 2007, 8:16pm UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/24 "2007-12-29T20:16:50Z")
[QUOTE=Max Torque] One thing my parents discovered cleaning out their house was a “pocket calculator”, [somewhat similar to this one](http://www.computermuseum.li/Testpage/Calc-Chadwick.htm), that my mother bought after she married my father to help her balance the checkbook. It worked by using the stylus on the side to slide the different numbers into position. [/QUOTE] Hee. I’ve got a slide rule, somewhere, with one of those things built into the back … ---
**Author:** ![Bosda\_Di\_Chi\_of\_Tricor](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bosda_di_chi_of_tricor/32/16845_2.png) [@Bosda\_Di\_Chi\_of\_Tricor](https://boards.straightdope.com/u/Bosda_Di_Chi_of_Tricor)\ **Post date:** [December 29, 2007, 11:35pm UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/25 "2007-12-29T23:35:05Z")
[QUOTE=Tapioca Dextrin] Why not go all the way and use a mechanical [PC](http://en.wikipedia.org/wiki/Moniac) :eek: [/QUOTE] WOW!! :eek: > [@](#): > > The MONIAC (Monetary National Income Automatic Computer) also known as the Phillips Hydraulic Computer and the Financephalograph, was created in 1949 by the New Zealander economist Bill Phillips to model the national economic processes of the United Kingdom, while Phillips was a student at the London School of Economics (LSE), The MONIAC was an analogue computer which used hydraulics to model the workings of an economy. > > The MONIAC was approximately 2 m high, 1.2 m wide and almost 1 m deep, and consisted of a series of transparent plastic tanks and pipes which were fastened to a wooden board. Each tank represented some aspect of the UK national economy and the flow of money around the economy was illustrated by coloured water. At the top of the board was a large tank called the treasury. Water (representing money) flowed from the treasury to other tanks representing the various ways in which a country could spend its money. For example, there were tanks for health and education. To increase spending on health care a tap could be opened to drain water from the treasury to the tank which represented health spending. Water then ran further down the model to other tanks, representing other interactions in the economy. Water could be pumped back to the treasury from some of the tanks to represent taxation. Changes in tax rates were modeled by increasing or decreasing pumping speeds > > MONIAC had been designed to be used as a teaching aid but was discovered also to be an effective economic simulator. Terry Pratchett put a version of this into _Making Money_, but I never dreamed it was **real**! ---
**Author:** ![Beware\_of\_Doug](https://avatars.discourse-cdn.com/v4/letter/b/278dde/32.png) [@Beware\_of\_Doug](https://boards.straightdope.com/u/Beware_of_Doug)\ **Post date:** [December 30, 2007, 12:00am UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/26 "2007-12-30T00:00:51Z")
In case anybody doesn’t know about [mechanical scanning television](http://earlytelevision.org/mechanical_tv.html), yes, there once was such an animal. A few nuts in [Britain](http://www.nbtv.wyenet.co.uk/), and one in the [USA](http://www.earlytelevision.org/yanczer.html), experiment with it even to this day. ---
**Author:** ![hajario](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hajario/32/171_2.png) [@hajario](https://boards.straightdope.com/u/hajario)\ **Post date:** [December 30, 2007, 12:21am UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/27 "2007-12-30T00:21:15Z")
[QUOTE=Rico] [Hours of fun playing with a Virtual Curta Calculator!](http://www.vcalc.net/curta_simulator_en.htm) (Requires Flash 6) [/QUOTE] One of my prized possessions is a near mint condition Curta II that I bought on Ebay a couple years ago. It’s an amazing machine. The life story of [Carl Herzstark](http://en.wikipedia.org/wiki/Curt_Herzstark) who invented the Curta is amazing as well. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [December 30, 2007, 12:35am UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/28 "2007-12-30T00:35:04Z")
Forgotten??? Right. Make me feel old. Slide Rules Nomographs Pocket adding Machines (the ones with moving slides, not the push0button kind) Manually extracting Square roots (and higher) Tables of Logarithms Buffon’s Needle and similar calculation-by-experiment methods ---
**Author:** ![Napier](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Napier](https://boards.straightdope.com/u/Napier)\ **Post date:** [December 30, 2007, 4:10pm UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/29 "2007-12-30T16:10:58Z")
Tables of logarithms? I often need to do approximate logs in my head. Here’s an easy way. Remember this list: 1, 1.25, 1.6, 2, 2.5, 3.2, 4, 5, 6.4, 8. These are 10^0.0, 10^0.1, 10^0.2, and so forth. Thus, the log10 of 700 must be about 2.85. When I check that with an electronic calculator, I get 2.8451. Not bad, eh? About 10 years ago I designed a slide rule to manage several slightly complicated calculations in the industry I was working in at the time. I found a company that still makes them, and had 3000 of them made. There were 4 simple multiplication scales, 5 unit conversion marks, and one special scale that essentially reported purity in terms like 99.5% or 5N7 (99.9997%). We passed hundreds out to possible customers so that they could compare our products with competing ones in a way that used a real and insightful figure of merit. ---
**Author:** ![Napier](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Napier](https://boards.straightdope.com/u/Napier)\ **Post date:** [December 30, 2007, 4:12pm UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/30 "2007-12-30T16:12:21Z")
P.S. I guess you can tell that John Napier was kind of a hero of mine. But my favorite thing that he did was publishing pamphlets arguing his view that the Pope was the Antichrist. ---
**Author:** ![Capt.Ridley\_s\_Shooting\_Party](https://avatars.discourse-cdn.com/v4/letter/c/cc9497/32.png) [@Capt.Ridley\_s\_Shooting\_Party](https://boards.straightdope.com/u/Capt.Ridley_s_Shooting_Party)\ **Post date:** [December 30, 2007, 6:21pm UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/31 "2007-12-30T18:21:25Z")
> [@](#): > > Buffon’s Needle and similar calculation-by-experiment methods I’d never heard of Buffon’s Needle (and the Noodle) before this. Thanks! Pretty interesting. ---
**Author:** ![Unintentionally\_Blank](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/unintentionally_blank/32/5418_2.png) [@Unintentionally\_Blank](https://boards.straightdope.com/u/Unintentionally_Blank)\ **Post date:** [December 30, 2007, 11:19pm UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/32 "2007-12-30T23:19:32Z")
Funny thing is: I’m glad you brought this up. My primary hobby these days is making shavings out of billet on a mill and lathe. My current project is a rotary mill (it spins the part to be worked on around an axis…it required making a worm gear and screw), one of the ways of recording angles precisely is with a vernier…but if you’re making it yourself, you also need to make the markings, and a vernier is part of the design. S’funny how much knowledge we no longer know. (My handbook, how to run a lathe, is the 1942 printing. The FIRST printing was in 1914. Most of the concepts were well known THEN. NOW, it’s all CNC. Not a bad thing, but a lot of the art’s been lost.) ---
**Author:** ![Unintentionally\_Blank](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/unintentionally_blank/32/5418_2.png) [@Unintentionally\_Blank](https://boards.straightdope.com/u/Unintentionally_Blank)\ **Post date:** [December 30, 2007, 11:31pm UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/33 "2007-12-30T23:31:57Z")
[QUOTE=Unintentionally Blank] Funny thing is: I’m glad you brought this up. My primary hobby these days is making shavings out of billet on a mill and lathe. My current project is a rotary mill (it spins the part to be worked on around an axis…it required making a worm gear and screw), one of the ways of recording angles precisely is with a vernier…but if you’re making it yourself, you also need to make the markings, and a vernier is part of the design. S’funny how much knowledge we no longer know. (My handbook, how to run a lathe, is the 1942 printing. The FIRST printing was in 1914. Most of the concepts were well known THEN. NOW, it’s all CNC. Not a bad thing, but a lot of the art’s been lost.) [/QUOTE] Gah. Rotary _table_. ---
**Author:** ![Lumpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lumpy/32/446_2.png) [@Lumpy](https://boards.straightdope.com/u/Lumpy)\ **Post date:** [December 30, 2007, 11:43pm UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/34 "2007-12-30T23:43:32Z")
[QUOTE=Rico] [Hours of fun playing with a Virtual Curta Calculator!](http://www.vcalc.net/curta_simulator_en.htm) (Requires Flash 6) [/QUOTE] Ok, I’m gonna’ need some help here. I’ve got most of how it works but not all. The buttons on the side input the working value, the top crank performs one operation per spin, and rotating the whole top multiplies the decimal place of the operation X10 per notch. The ringed lever resets the number of operations count and the result count to zero. That leaves pulling out the top crank, and the extra toggle switch. I gather that these somehow invert the operations you’re performing so you can do subtraction and division; but I haven’t worked out how. Anyone? ---
**Author:** ![Tuckerfan](https://avatars.discourse-cdn.com/v4/letter/t/eada6e/32.png) [@Tuckerfan](https://boards.straightdope.com/u/Tuckerfan)\ **Post date:** [December 31, 2007, 12:05am UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/35 "2007-12-31T00:05:58Z")
[QUOTE=Unintentionally Blank] Funny thing is: I’m glad you brought this up. My primary hobby these days is making shavings out of billet on a mill and lathe. My current project is a rotary mill (it spins the part to be worked on around an axis…it required making a worm gear and screw), one of the ways of recording angles precisely is with a vernier…but if you’re making it yourself, you also need to make the markings, and a vernier is part of the design. S’funny how much knowledge we no longer know. (My handbook, how to run a lathe, is the 1942 printing. The FIRST printing was in 1914. Most of the concepts were well known THEN. NOW, it’s all CNC. Not a bad thing, but a lot of the art’s been lost.) [/QUOTE] Not really, [you can find much of it on Google! 😉](http://boards.straightdope.com/sdmb/showthread.php?t=447855) Also, if you _haven’t_ mosied over to [Homeshop Machinist’s boards](http://bbs.homeshopmachinist.net/), you outta. There’s more than a few of the old timers there who bitch about how stupid the new fangled dial calipers are making the kids these days. 😃 ---
**Author:** ![Unintentionally\_Blank](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/unintentionally_blank/32/5418_2.png) [@Unintentionally\_Blank](https://boards.straightdope.com/u/Unintentionally_Blank)\ **Post date:** [December 31, 2007, 12:15am UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/36 "2007-12-31T00:15:59Z")
Haven’t spent much time on HSM, I spend more of it on Popular Machinist…and actually, since I got the South Bend restored, don’t spend a lot of time on the forums. I need to get back out to the garage, but it’s pretty cold out there. Here’s my stunningly cool link of the week: The Kinematic Models for design digital library: [http://kmoddl.library.cornell.edu/](http://kmoddl.library.cornell.edu/) ---
**Author:** ![GoneTheSun](https://avatars.discourse-cdn.com/v4/letter/g/a183cd/32.png) [@GoneTheSun](https://boards.straightdope.com/u/GoneTheSun)\ **Post date:** [December 31, 2007, 1:03am UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/37 "2007-12-31T01:03:07Z")
I’m surprised it took so long for [slide rules](http://www.sliderule.ca/) to get mentioned. You might also consider the old surveying equipment that was used prior to electronic distance measurement and global positioning systems. Examples would be [transits](http://cgi.ebay.com/SOLID-BRASS-SURVEY-TRANSIT-HEAD-EXCELLENT-WORKING-ORDER_W0QQitemZ270199013911QQihZ017QQcategoryZ55807QQcmdZViewItem) and [steel tapes](http://celebrating200years.noaa.gov/distance_tools/theb1670.html). With the old steel tapes, surveys would have to correct distances measured for air temperature, tension and sag in the tape, and other factors (been a while since I took my old survey class, but seems like there were 7 factors including human error). Probably very few fields have been so completely revolutionized in the past 20 years as land surveying, due to the advent of inexpensive lasers, satellites, and computers. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [December 31, 2007, 1:47am UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/38 "2007-12-31T01:47:43Z")
> [@](#): > > Tables of logarithms? I often need to do approximate logs in my head. Here’s an easy way. Martin Gardner gave a somewhat different method in his Mathematical Games column many years ago/ When I was an undergrad, there was a guy who could accurately reel off three-place logs from memory. He did surprisingly well when druink. ---
**Author:** ![Lumpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lumpy/32/446_2.png) [@Lumpy](https://boards.straightdope.com/u/Lumpy)\ **Post date:** [December 31, 2007, 1:52am UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/39 "2007-12-31T01:52:02Z")
[QUOTE=Lumpy] Ok, I’m gonna’ need some help here. I’ve got most of how it works but not all. The buttons on the side input the working value, the top crank performs one operation per spin, and rotating the whole top multiplies the decimal place of the operation X10 per notch. The ringed lever resets the number of operations count and the result count to zero. That leaves pulling out the top crank, and the extra toggle switch. I gather that these somehow invert the operations you’re performing so you can do subtraction and division; but I haven’t worked out how. Anyone? [/QUOTE] Duh, never mind. Finally got it\*. Pulling out top crank switches value added to negative; toggle switch changes whether revolution counter increments or de-increments. \*Don’t you wish if you were going to understand something, it would come to you immediately, not hours later? ---
**Author:** ![ElvisL1ves](https://avatars.discourse-cdn.com/v4/letter/e/5daacb/32.png) [@ElvisL1ves](https://boards.straightdope.com/u/ElvisL1ves)\ **Post date:** [December 31, 2007, 3:42pm UTC](https://boards.straightdope.com/t/forgotten-analog-technology/431433/40 "2007-12-31T15:42:26Z")
Doesn’t anybody use an abacus anymore? Well, maybe not, used ta be an expert at it wouldn’t need an actual abacus anymore, like a chess expert doesn’t need a chess set. [Previous page](https://boards.straightdope.com/t/forgotten-analog-technology/431433.md?page=1) [Next page](https://boards.straightdope.com/t/forgotten-analog-technology/431433.md?page=3)