Slide rules

Kestas

Staff member
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13,959
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The Motor City
I just had an interesting morning. One of the techs brought in an old slide rule he inherited. I was the only one trained (and old enough) how to use one, and found myself surrounded by all the techs who marveled at how that thing works. I feel very old.
 
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15,410
Location
Santa Barbara, CA
Nice!! I have my grandpa's from when he worked for Brewster, Vertol, and Boeing. He showed me how to use it and I brought it into school and the teacher got mad. We were not allowed to use calculators, teacher did not say anything about slide rules. BTW for reference I was born in 1983.
 
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13,616
Location
Frisco, TX
We got my Dad a really nice one for Christmas last year. He loves it and is exceptionally fast with it. It is a very neat invention.
 
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17,238
Location
Upper Midwest
I think I can still multiply (and probably divide) on one but that would be it. Back in high school (I graduated in '79) calculators were coming into use but slide rules and log tables were still prevalent. All the chemistry classrooms had enormous slide rules mounted above the chalkboard for the teacher to use during lecture.
 
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beaver land EH?
I was taught by ma dad to use slide rules (in the 80s, of course) and since then I have gathered a handful of them just for fun. Imagine that astronauts in the 60s used slide-rule to calculate their flight trajectory and still managed to land on the moon and back... *facinating* Q.
 
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17,238
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Upper Midwest
Well the astronauts in the space capsules and the lunar module did not use slide rules to compute flight trajectories. That was done both on the ground and in flight via their computers. It isn't as if Buzz Aldrin was furiously computing logarithms on his slide rule while Armstrong was piloting to the lunar surface wink
Originally Posted By: Quest
I was taught by ma dad to use slide rules (in the 80s, of course) and since then I have gathered a handful of them just for fun. Imagine that astronauts in the 60s used slide-rule to calculate their flight trajectory and still managed to land on the moon and back...
 
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OH
...and the computer in the LEM flaked out when it suffered task overload and Armstrong had to fly the thing manually to a safe landing before running out of the descent fuel needed for braking, as they very nearly did.
 

MolaKule

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21,908
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Iowegia - USA
Originally Posted By: Kestas
I just had an interesting morning. One of the techs brought in an old slide rule he inherited. I was the only one trained (and old enough) how to use one, and found myself surrounded by all the techs who marveled at how that thing works. I feel very old.
I still have my Picket "yellowback" from undergrad school. I took it into work one day and the engineers said they had heard about slide rules but never used one. After a few quick calcs, they seemed amazed at how quickly one could calculate on, as they called, an "analog" computer. grin2
 
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Location
Florida
I was required to have one for 8th grade chemistry class (this would have been around 1978). Calculators were not allowed. I'm not sure where you could buy one now-a-days.
 
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Champlain/Hudson Valley
Hello, I was in university in 1974 when a teacher brought in a slide rule and asked if, "...anybody knew what this was?" We all got it right. Then he told us that K&E (I think) had just announced they were discontinuing production. I knew a shy 3% of what a slide rule could do. Kira
 
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DFW
I had a TI30 calculator from 1978-1983 and I have had an HP 15C since 1983 - still use it every day. That's as close to a slide rule as I ever need to get.
 
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17,931
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NH
I'm about 37 so I came after slide rules died off. I still like them, cool idea, lacking in precision in today's world but still likely good enough for a large number of tasks. When I see one cheap at a fleamarket/hamfest I will buy it. I have two or three now I think, and a manual or two. I know the mechanics behind it, but have never take the time to master it. I know two of the scales but the rest... not so much. Sine, cosine, etc. What I usually do is first do a calculation that I know the result to, that way I know I'm on the right scales. But by then it would have been faster to either get a calculator or do it by hand!
 
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North America
Originally Posted By: Kestas
I just had an interesting morning. One of the techs brought in an old slide rule he inherited. I was the only one trained (and old enough) how to use one, and found myself surrounded by all the techs who marveled at how that thing works. I feel very old.
Age doesn't matter, as noted above. You had the training and ability. Don't sell the slide rule short -after all, the SR71 was designed using it.
Originally Posted By: chainblu
I was required to have one for 8th grade chemistry class (this would have been around 1978). Calculators were not allowed. I'm not sure where you could buy one now-a-days.
They sell circular ones for pilots. [hijack]
Originally Posted By: fdcg27
...and the computer in the LEM flaked out when it suffered task overload and Armstrong had to fly the thing manually to a safe landing before running out of the descent fuel needed for braking, as they very nearly did.
Which is why we should never have a pilotless airliner! [/hijack]
 
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3,203
Location
Southeastern, PA
My favorite instructor, Professor Buzzard, had us learn the slide rule in a first-year engineering course back in '77. Then we went on to learn computer programming. I always appreciated the practicality of his lessons. He was a good teacher...
 
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983
Location
Florida
Originally Posted By: Kuato
They sell circular ones for pilots.
Oh yes, Kuato. I have an E6B. Very handy device. Mine is packed away with my log books and other manuals. (I no longer fly)
 
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2,103
Location
British Columbia, Canada
I have an old very high quality Hughes-Owens bamboo slide rule, with leather case and all, the kind engineers admired. We were expected to be fairly accurate in our calculations, even under exam pressure. Interestingly it also says Sun Hemmi Japan. When I graduated from engineering, calculators were almost unknown and extraordinarily expensive. Ecotourist
 
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17,238
Location
Upper Midwest
Armstrong having to fly the LEM was not due to the computer overload, it was due to the pre-programmed landing area being filled with boulders "the size of houses". The computer was still quite able to perform the required functions despite being overloaded by the rendezvous radar. The executive overload alarms, although annoying and distracting were not dangerous to the mission - correctly called out by Sy Liebergot.
Originally Posted By: fdcg27
...and the computer in the LEM flaked out when it suffered task overload and Armstrong had to fly the thing manually to a safe landing before running out of the descent fuel needed for braking, as they very nearly did.
 
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