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Panoramix has trouble seeing beyond his box. If there is one feature common to almost all new European production boats today it is a sprit of some dimension. Same can be said of pretty much any high

Steele: Yes, that's the flipper.. Look dejected. The cutter will be a bit heavy but not enough to worry about. Not as much as Neil anticipated. Iwill revise the ballast for no. 2. I spec'd 1

Whisper ain't that fat. Just stupid.  

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I'd thought of naming my boat "Lilly," after my grandmother.  But the main reason I didn't was that I'd then have to choose which grandmother or great-grandmother's name to use. Now it's obvious! Just build a boat for each of them!  D'Oh!

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On 9/29/2017 at 5:10 AM, sailforbeer said:

/sarcasm font on/

Bob, the whole fucking horizon is bow down.  Easily by .25".  Can you adjust the planet's trim ballast too?

Thanks; I don't want to fall off.

 

If you are familiar with Rick and Morty then you will get this video, if you aren't...well you should be.

 

https://youtu.be/1X-ZVOYwNLU?t=1s

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It occured to me that young Mr Porter and some other posters may not know what a planimeter is. It's a mechanical device to measure area, like section shapes on a lines drawing. Took me a while to find mine...it was hiding behind 2 sextants, 2 Walker trailing logs, and a vintage handbearring compass. 

22256536_10155872187411579_8320461019259

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Kocher:

You are sooooo wrong. Will P, was introduced to the planimeter when he was at my shack. He used it. As did my Italian intern. Do not underestimate me.

 

I never saw an integrator in person. I have a photo of Uffa Fox bending over one but that's as close as I have come.

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I never saw one in person either. When my professor told us of its existence, I sort of groaned.

I never used a planimeter professionally. Well not exactly. I did use the planimeter on my first commission. But I was still in school.
Because the planimeter doesn't do all the inertia stuff, it wasn't much of a help in commercial stuff, like for instance doing a lost buoyancy damage stability calculation...so you just simpson or tchebycheff to your heart's content!

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10 minutes ago, Bob Perry said:

I never saw an integrator in person. I have a photo of Uffa Fox bending over one but that's as close as I have come.

Is thet howe you niewe he hade centroides?  Seemes kinda pearsonalle...... juste sayeng.            :)

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Yeah, that's funny Snagger.

The integrator was an amazing piece of machinery. I can't imagine what they cost.

I bought my first planimeter for $100. I found one in a pawn shop. I was probably 18 years old. $100 was a lot of dough at that time.

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I paid $300 for my first digital planimeter. It's still going strong. When it goes. Which is not very often anymore. But for many years I hardly ever put it away. I'll keep it so that when I'm gone someone going through my stuff will go, "WTF?".

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3 minutes ago, Bob Perry said:

I paid $300 for my first digital planimeter. It's still going strong. When it goes. Which is not very often anymore. But for many years I hardly ever put it away. I'll keep it so that when I'm gone someone going through my stuff will go, "WTF?".

Pretty much everything I own is "WTF?"

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46 minutes ago, Bob Perry said:

Kocher:

You are sooooo wrong. Will P, was introduced to the planimeter when he was at my shack. He used it. As did my Italian intern. Do not underestimate me.

 

I never saw an integrator in person. I have a photo of Uffa Fox bending over one but that's as close as I have come.

I should have known. We're they being bad? You catch them cussing and made them use a planimeter?

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33 minutes ago, Bob Perry said:

I guess we are getting to that age. The Golden WTF Years.

You're lucky. We don't have children so we're stuck with a lot of our crap. Our parents sure did a WTF dump on us.

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I'm reading a biography of Claude Shannon, of "Shannon Entropy" and "Shannon Information" fame. Though he never cared about taking credit, it was his idea to use bits and bytes to do computing.

Before getting the idea he worked in a lab that had one of the best analog computers. I never realized that "analog" is related to the original definition, "comparable." The idea was that the computer was a model, an "analog," of the real physical world. It consisted of integrators that were used to model differential equations.

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2 hours ago, kdh said:

I'm reading a biography of Claude Shannon, of "Shannon Entropy" and "Shannon Information" fame. Though he never cared about taking credit, it was his idea to use bits and bytes to do computing.

Before getting the idea he worked in a lab that had one of the best analog computers. I never realized that "analog" is related to the original definition, "comparable." The idea was that the computer was a model, an "analog," of the real physical world. It consisted of integrators that were used to model differential equations.

If you're at all technically inclined and haven't read his "The Mathematical Theory of Communication", make sure you do. It's short and sweet.

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12 hours ago, fastyacht said:

That is for sure!
My first 11c was $130 and that was a lot of money, too! And that was after all that inflation!

Whaddaya mean, "first?" Mine is still going after 35 years.  OK, the display is getting a little leaky and the functions are worn off some of the keys.  But it still works fine. Every day.  

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1 minute ago, toddster said:

Whaddaya mean, "first?" Mine is still going after 35 years.  OK, the display is getting a little leaky and the functions are worn off some of the keys.  But it still works fine. Every day.  

Haha well if I hadn't left it on an airplane in 1995 I guess it would still be...

...actually that was my third by then--because twice I'd sent it back to Corvallis for repairs. Even then, they simply sent you a new one and said on the invoice "replaced logic board and display LCD" but actually just swapped it out :-)

 

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1 hour ago, IStream said:

If you're at all technically inclined and haven't read his "The Mathematical Theory of Communication", make sure you do. It's short and sweet.

http://math.harvard.edu/~ctm/home/text/others/shannon/entropy/entropy.pdf

Quote

A Mathematical Theory of Communication
By C. E. SHANNON INTRODUCTION

THE recent development of various methods of modulation such as PCM and PPM which exchange bandwidth for signal-to-noise ratio has intensified the interest in a general theory of communication. A basis for such a theory is contained in the important papers of Nyquist1 and Hartley2 on this subject. In the present paper we will extend the theory to include a number of new factors, in particular the effect of noise in the channel, and the savings possible due to the statistical structure of the original message and due to the nature of the final destination of the information.

The fundamental problem of communication is that of reproducing at one point either exactly or approximately a message selected at another point. Frequently the messages have meaning; that is they refer to or are correlated according to some system with certain physical or conceptual entities. These semantic aspects of communication are irrelevant to the engineering problem. The significant aspect is that the actual message is one selected from a set of possible messages. The system must be designed to operate for each possible selection, not just the one which will actually be chosen since this is unknown at the time of design.

If the number of messages in the set is finite then this number or any monotonic function of this number can be regarded as a measure of the information produced when one message is chosen from the set, all choices being equally likely. As was pointed out by Hartley the most natural choice is the logarithmic function. Although this definition must be generalized considerably when we consider the influence of the statistics of the message and when we have a continuous range of messages, we will in all cases use an essentially logarithmic measure.

The logarithmic measure is more convenient for various reasons:

  1. It is practically more useful. Parameters of engineering importance such as time, bandwidth, number of relays, etc., tend to vary linearly with the logarithm of the number of possibilities. For example, adding one relay to a group doubles the number of possible states of the relays. It adds 1 to the base 2 logarithm of this number. Doubling the time roughly squares the number of possible messages, or doubles the logarithm, etc.
  2. It is nearer to our intuitive feeling as to the proper measure. This is closely related to (1) since we intuitively measures entities by linear comparison with common standards. One feels, for example, that two punched cards should have twice the capacity of one for information storage, and two identical channels twice the capacity of one for transmitting information.
  3. It is mathematically more suitable. Many of the limiting operations are simple in terms of the logarithm but would require clumsy restatement in terms of the number of possibilities.

The choice of a logarithmic base corresponds to the choice of a unit for measuring information. If the base 2 is used the resulting units may be called binary digits, or more briefly bits, a word suggested by J. W. Tukey. A device with two stable positions, such as a relay or a flip-flop circuit, can store one bit of information. N such devices can store N bits, since the total number of possible states is 2^N and log2 2^N = N.

 

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4 hours ago, kdh said:

I'm reading a biography of Claude Shannon, of "Shannon Entropy" and "Shannon Information" fame. Though he never cared about taking credit, it was his idea to use bits and bytes to do computing.

Before getting the idea he worked in a lab that had one of the best analog computers. I never realized that "analog" is related to the original definition, "comparable." The idea was that the computer was a model, an "analog," of the real physical world. It consisted of integrators that were used to model differential equations.

Is this the "A Mind at Play" book?  I'm looking forward to reading that!  Shannon is one of my personal heroes.  If you haven't already read it, "The Information" by James Gleick is very good and has a nice chapter about Shannon.

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2 minutes ago, valis said:

Is this the "A Mind at Play" book?  I'm looking forward to reading that!  Shannon is one of my personal heroes.  If you haven't already read it, "The Information" by James Gleick is very good and has a nice chapter about Shannon.

Yes, "A Mind at Play."

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I have my Dad's Curta Calculator, which he bought for his engineering work at the Chevron refinery in Richmond, CA.  It's a hand cranked, mechanical calculator that performs just about any operation by manipulating dials and buttons.  There's no plastic, so it weighs a ton.  The man who invented it, Curta, designed it in his mind while in a German Concentration camp, and then built it after his liberation.  The machine is in it's original box, with the receipt included.  My dad bought it for about $100.00.  Today, it's worth about $100.00.  I imagine that he tried it once or twice, then realized that his slide rule was ten times faster and put it on the shelf until he died.  I have shown it to some of my colleagues in the math department asking them if they can tell me what it is.  The response, essentially, is WTF?

 

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We used to have a Friden Mechanical Calculator in the family.  Somehow, it ended up at our house, but nobody had a clue how to use it. I think I broke it by entering a large calculation that it could never finish. It made a wonderful racket.  

friden01large.jpg

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48 minutes ago, Hawaiidart said:

I have my Dad's Curta Calculator, which he bought for his engineering work at the Chevron refinery in Richmond, CA.  It's a hand cranked, mechanical calculator that performs just about any operation by manipulating dials and buttons.  There's no plastic, so it weighs a ton.  The man who invented it, Curta, designed it in his mind while in a German Concentration camp, and then built it after his liberation.  The machine is in it's original box, with the receipt included.  My dad bought it for about $100.00.  Today, it's worth about $100.00.  I imagine that he tried it once or twice, then realized that his slide rule was ten times faster and put it on the shelf until he died.  I have shown it to some of my colleagues in the math department asking them if they can tell me what it is.  The response, essentially, is WTF?

 

IIRC, the Curta Calculators were popular with auto rally navigators in the 60s. I recall seeing ads for them in automotive magazines. I think marine navigators used a circular slide rule...pretty sure I have one in a box somewhere.

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22 minutes ago, toddster said:

We used to have a Friden Mechanical Calculator in the family.  Somehow, it ended up at our house, but nobody had a clue how to use it. I think I broke it by entering a large calculation that it could never finish. It made a wonderful racket.  

friden01large.jpg

That looks amazing. It's like modern era steam punk.

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My Dad's good buddy was an HP sales guy when the first $300 calculators came out.  First time I ever saw one he brought it to the house.  Part of his pitch was to show how rugged they were.  He chucked it across the room to the far wall, which he'd done numerous time on demos.  The case broke and parts flew to our great shock.  He laughed and said it's a good thing it broke in front of us instead of a real customer.  

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11 minutes ago, RKoch said:

That looks amazing. It's like modern era steam punk.

The answer is a big number too. I hope it wasn't your uncle's tax liability? :unsure:

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1 hour ago, toddster said:

We used to have a Friden Mechanical Calculator in the family.  Somehow, it ended up at our house, but nobody had a clue how to use it. I think I broke it by entering a large calculation that it could never finish. It made a wonderful racket.  

friden01large.jpg

The Curta is about the size of a soup can.  It's neat, but my Dad got it in 1963.  By the end of the decade, thanks to the Space Race and NASA, digital calculators were on the scene.  The first I remember seeing in mass was the TI.  Like the first cell phones, it was the size of a brick.  I remember asking my parents to buy me one.  My dad tossed me a spare slide rule and told that it was all I'd ever need.  

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1 hour ago, Kenny Dumas said:

My Dad's good buddy was an HP sales guy when the first $300 calculators came out.  First time I ever saw one he brought it to the house.  Part of his pitch was to show how rugged they were.  He chucked it across the room to the far wall, which he'd done numerous time on demos.  The case broke and parts flew to our great shock.  He laughed and said it's a good thing it broke in front of us instead of a real customer.  

My dad had an early HP that was $300. It was heavy. Leather case. Not particularly big.

Edit: This is it. HP-35. I used it in college.

35v43q.jpg

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30 minutes ago, Hawaiidart said:

The Curta is about the size of a soup can.  It's neat, but my Dad got it in 1963.  By the end of the decade, thanks to the Space Race and NASA, digital calculators were on the scene.  The first I remember seeing in mass was the TI.  Like the first cell phones, it was the size of a brick.  I remember asking my parents to buy me one.  My dad tossed me a spare slide rule and told that it was all I'd ever need.  

Yep. I've never used one, but I remember the ads. IDK what they cost back in the 60s...$100 or so?

image.jpg

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1 minute ago, kdh said:

My dad had an early HP that was $300. It was heavy. Leather case. Not particularly big.

Edit: This is it. HP-35. I used it in college.

35v43q.jpg

My father got an early calculator in the early 70s. I don't remember the make, but it was about $100 and did addition, subtraction, multiplication, and division. Just a few years later could buy one with same functions for under $10. I still have one, it still works. Also still have a TI-55 from college days and a couple other assorted calculators. Not sure if they still work.

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1 minute ago, kdh said:

My dad had an early HP that was $300.

I had a -35, and then bought a 41CV when they came out (1979?)  I remember thinking "this thing changed my life"..... not only because it was programmable for work (I was doing structural stuff at an engineering company at the time) but... because when the "nav pack" came out, it reduced the workload of celestial nav by... a huge amount.  No need to carry around volumes of sight-reduction tables (HO-229) and almanacs, just punch in the numbers and get the LOPs.  Magic.

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2 hours ago, Hawaiidart said:

I have my Dad's Curta Calculator, which he bought for his engineering work at the Chevron refinery in Richmond, CA.  It's a hand cranked, mechanical calculator that performs just about any operation by manipulating dials and buttons.  There's no plastic, so it weighs a ton.  The man who invented it, Curta, designed it in his mind while in a German Concentration camp, and then built it after his liberation.  The machine is in it's original box, with the receipt included.  My dad bought it for about $100.00.  Today, it's worth about $100.00.  I imagine that he tried it once or twice, then realized that his slide rule was ten times faster and put it on the shelf until he died.  I have shown it to some of my colleagues in the math department asking them if they can tell me what it is.  The response, essentially, is WTF?

 

A quick search of EBay says it is worth considerably more than $100....

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19 minutes ago, kdh said:

My dad had an early HP that was $300. It was heavy. Leather case. Not particularly big.

Edit: This is it. HP-35. I used it in college.

35v43q.jpg

My dad had the same one. The photo brings back memories. To put it completely in perspective, that $300 from the mid 70s could buy a well configured iMac today. (or 2 well configured windows boxes)

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1 hour ago, RKoch said:

Yep. I've never used one, but I remember the ads. IDK what they cost back in the 60s...$100 or so?

image.jpg

$100.00 is what is says on the receipt from 1963.  I looked on Ebay and Craigslist and found them for $100.00 in 2016.

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I recognise that photo of the 35. It is from hpmuseum.org.
If you are a 41CX afficionado that is one of three places to visit. The other is Viktor toth's site,  rskey.org and also Warren Furlow's site http://www.hp41.org/
 

  and you can run these on your phones now.
HrastProgrammer and Christoph Giesselink. Thomas Okken and others have made amazing emulators and in some cases simulators.

http://www.hpcc.org/calculators/hp41.html#emulators

In fact you can even emulate the 41, on a 48!:

http://www.hrastprogrammer.com/hp42x/
(you can also emulate the 27s, and the 42s thanks to Thomas Okken, but you do have to have a working one of your own for the ROM dump....due to copyright)

 

http://thomasokken.com/free42/

Christoph mad nonpareil which even emulates the Classics such as the 35!

http://hp.giesselink.com/

http://nonpareil.brouhaha.com/

 


The 42s becomes a fantastic tool on a modern platform--because you get I/O and ability to load / unload programs!  This was crippled back in the day because they didn';t want to hurt sales of the 41 platform....

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6 minutes ago, toddster said:

I keep getting a warning that the 15c emulator app is going to stop working if they don't update it.  I think the new iOS upadate kills all 32bit apps?  

There's a bunch of different 15c implementations. Some are sketchy as I remember. One is by HP. They released a brand-new 15C a few years ago! It was a labor of love by some members of the always at risk calculator group at HP. They managed to get the ROM somehow (that had been mysteriously "missing" for a long time--I can';t remember the details now) and used the new hardware that was developed for the 12C platimum

The HP company's own emulator came out of that.


This was an absolute surprise that it happened at all. But a thrill.

 

I like Okken/ Hrast/Giesselink's work. They are so totally committed to this stuff.

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4 minutes ago, Bob Perry said:

I just got a big new batch of photos from last Thursday. Friday forecast is for 10 to 15 knots. We are going sailing.

37501992021_9bc11d939e_k.jpgwa 2 by robert perry, on Flickr

Sweet, I hope you guys get enough pressure to be fully powered up and can find the rudder stall spot.


I'm headed to Naples FL to check a building that got slammed by Irma. Hoping to get out on the water one day this weekend or next week.

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1 hour ago, Hawaiidart said:

$100.00 is what is says on the receipt from 1963.  I looked on Ebay and Craigslist and found them for $100.00 in 2016.

I looked today and got a bit of a shock. I was thinking of buying one to go with my abacus and the various slide rules I have.

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4 hours ago, Hawaiidart said:

$100.00 is what is says on the receipt from 1963.  I looked on Ebay and Craigslist and found them for $100.00 in 2016.

I just looked on eBay now, prices run $900-2000. Just the instruction manual runs $58. That's pretty amazing. 

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Nice boat pic BP.

Calculators bring back memories. I studied land surveying at university, and some of the math was very complex = especially least squares statistical analysis of geodetic survey measurements. HP's were reasonably common. I broke the mold I guess (or I was just plain lazy). Lecturers told me whatever I could program I could take into exams with me. We even used it on field trips for all competing student teams for quick results. I had the PC-1401 (early model with scientific buttons instead of financial) , with the micro cassette for storing programs and the thermal printer. Way back in 1984.

Sharp-PC-1421-M.JPG

PC-1421: This machine was also released in 1984. As the PC-1401, it had 4.2 KB RAM (3454 for BASIC). However, it was powered by a later release of the CPU and clocked with a higher clock rate (768 kHz), which made it one third faster. From the software's point of view,it was equipped with special math functions for business/financial matters. Together with the PC-1401, the CE-126P thermal printer and micro cassette interface unit was introduced. It was alkaline battery powered and could print 24 characters per line on special thermal paper. 

 

Not that I would ever have used rem statements to record important things that were hard to remember during an exam......

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16 minutes ago, dfw_sailor_wannabe said:

Nice boat pic BP.

Calculators bring back memories. I studied land surveying at university, and some of the math was very complex = especially least squares statistical analysis of geodetic survey measurements. HP's were reasonably common. I broke the mold I guess (or I was just plain lazy). Lecturers told me whatever I could program I could take into exams with me. We even used it on field trips for all competing student teams for quick results. I had the PC-1401 (early model with scientific buttons instead of financial) , with the micro cassette for storing programs and the thermal printer. Way back in 1984.

Sharp-PC-1421-M.JPG

PC-1421: This machine was also released in 1984. As the PC-1401, it had 4.2 KB RAM (3454 for BASIC). However, it was powered by a later release of the CPU and clocked with a higher clock rate (768 kHz), which made it one third faster. From the software's point of view,it was equipped with special math functions for business/financial matters. Together with the PC-1401, the CE-126P thermal printer and micro cassette interface unit was introduced. It was alkaline battery powered and could print 24 characters per line on special thermal paper. 

 

Not that I would ever have used rem statements to record important things that were hard to remember during an exam......

Sharps machines had far more firepower per dollar than HP. So did Casio actually.
Programmed in BASIC, they were more universally versatile for programming, and they had more memory. And I/O as you point out.
Radio Shack sold the SHARP products under the Radio Shack name.
My European colleagues had these Casio and Sharps and they could run circles around my 11c for the same price.
There is a calculator expert who in addition to being a member of HPCC (a longstanding Hewlett Packard user's club) is also an expert on these Sharps. He has written some great articles on them. Name: Valentin Albillo. He is an extremely skilled programmer and you can learn a lot from his interesting articles.

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Anyone remember a nixie tube display desk calculator wired to a shared central processor that did the calculations? I think it might have been Sharp.

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3 hours ago, Grey Dawn said:

Anyone remember a nixie tube display desk calculator wired to a shared central processor that did the calculations? I think it might have been Sharp.

First year physics at uni, we had HP desktop calculators/computers to help run experiments; they had nixie tubes. Forgot all about them! Can't remember the HP product number.

The (rich) nerds had HP35s, I had a slide rule - much easier than log tables.......

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9 hours ago, Grey Dawn said:

Anyone remember a nixie tube display desk calculator wired to a shared central processor that did the calculations? I think it might have been Sharp.

Yes.  Monroe as I recall.  With a card reader.  Programming was done by marking cards with a pencil to encode instructions and data.

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7 hours ago, Fleetwood said:

First year physics at uni, we had HP desktop calculators/computers to help run experiments; they had nixie tubes. Forgot all about them! Can't remember the HP product number.

The (rich) nerds had HP35s, I had a slide rule - much easier than log tables.......

HP - 12C  perhaps ?

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12 hours ago, Grey Dawn said:

Anyone remember a nixie tube display desk calculator wired to a shared central processor that did the calculations? I think it might have been Sharp.

That was a Wang (No Kidding)  Don't remember any card slots, but it was a 6-function with 3 or 4 memories.  One could do least-squares fits without writing down intermediates!  OK, OK, but that was a big deal way back when.  There was a self-test procedure that would take over the central processor for a couple of minutes.  Very useful for pissing off recalcitrant office partners...

Wang moved onto dedicated word processors, then kinda spaced out when PCs came out.  

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I remember the Wang! Our high school advanced sciences class had one that we did orbital calculations with and plotted the results in chalk on the floor. It had a tape cassette of sorts that the programming got written to which would loop over and over to give the plot point results. Pretty much a class of nerds it was and imagine the bullying that we got when the kool kids found out the name of our little computer.

'Hey Billy, you been playing with your WANG again in class?'

Plain old cassette?

Image result for wang computers

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Speaking of tube (while we wait for more pics Bob ;)   ).....

The tektronics 4014 was a really cool machine, in the early '70s. It had a 'storage' screen, which means when a line was drawn, it stayed on the screen permanently until the screen was reset. A lot like a etch a sketch. This was because memory was so expensive back then that raster graphics was prohibitive.

tek4014_01.JPG

They were still in use at my university in the mid '80s because virtually nothing else could match the precision and fineness of the display. Although not pixel based, it gave the equivalent of 4096 x 4096 resolution.  And the only plot color you got was green. The scary part was way back then the 4014 cost about $9k, in today's dollars about $50k.

Here's a 12 second clip that shows what the screen looked like when drawing a map projection of the world (and occulation of pluto)

 

 

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40 minutes ago, dfw_sailor_wannabe said:

Speaking of tube (while we wait for more pics Bob ;)   ).....

The tektronics 4014 was a really cool machine, in the early '70s. It had a 'storage' screen, which means when a line was drawn, it stayed on the screen permanently until the screen was reset. A lot like a etch a sketch. This was because memory was so expensive back then that raster graphics was prohibitive.

tek4014_01.JPG

They were still in use at my university in the mid '80s because virtually nothing else could match the precision and fineness of the display. Although not pixel based, it gave the equivalent of 4096 x 4096 resolution.  And the only plot color you got was green. The scary part was way back then the 4014 cost about $9k, in today's dollars about $50k.

Here's a 12 second clip that shows what the screen looked like when drawing a map projection of the world (and occulation of pluto)

 

 

Yep. Basement of the Engineering building at college had several Tektronix. Very nice resolution graphics, but only 16K. I think a few were only 8K. This was early 80s. There was a cassette type machine, the cassettes were about size of VHS tapes. Stone ages.

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HP-11C
The HP-11C is a mid-range scientific programmable calculator.

HP-15C
The HP-15C is a high-end scientific programmable with a root-solver and numerical integration, produced between 1982 and 1989. It is also able to handle complex numbers and matrix operations. Although long being discontinued its continued popularity among users triggered Hewlett-Packard to offer a HP 15c Limited Edition remake of the calculator in 2011.

My wife and I both had 15Cs when we met. We were star crossed, for sure.:wub:

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43 minutes ago, kdh said:

HP-11C
The HP-11C is a mid-range scientific programmable calculator.

HP-15C
The HP-15C is a high-end scientific programmable with a root-solver and numerical integration, produced between 1982 and 1989. It is also able to handle complex numbers and matrix operations. Although long being discontinued its continued popularity among users triggered Hewlett-Packard to offer a HP 15c Limited Edition remake of the calculator in 2011.

My wife and I both had 15Cs when we met. We were star crossed, for sure.:wub:

HP sells a great 15C emulator for Android for about $15, at least when I bought it. On a large screen phone it's almost the right size too.

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Bob: the 11C was the fist of the Voyager series produced. The 10c (lower price point) 12c (financial) and 15c nd of course 16c (computer science) followed.
The 15c is much more powerful. Possibly the most clever complex number and matrix implementation ever.

The 12C is no small thing either. The reason it has the crappy programming model shared with the 10C is that hte financial solver sopped up a lot of memory real estate.

Algebraic:
HP made a whole line of algebraic calculators starting in the 1987. the first was the clambshell 18C which althoug ha "c" was business oriented.
The Algebraic line (all in the "Pioneer" form factor) was 10b, 14b, 17b,  20s, 21s, 22s and the top of the line 27s. The 19b was the top of the line financial and shared the clambshell of the slightly earlier18c.
Interestingly their first desktop calculatoar was *also* algebraic--but handled all internally in RPN and converted back and forth for input anddisplay. Memory was expensive back then.

 

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