Math help[NA]

Discussion in 'Technical Corner' started by Let'sgoflying!, Nov 29, 2021.

  1. Brad W

    Brad W Cleared for Takeoff

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    oh, my old friend!
    I still have my 11C, bought in approx 1985 timeframe. I toted and punched on that thing through all of college and many years on the job. Retired it a while back because the LCD is leaking black around the edges(?) I still have it though, and it works.
    A few years back when my FIL passed, my SIL was cleaning out and was going to toss his 15C.... I yelled "NO!!! that thing is valuable in some circles"....so I've got that one too. It's in much better condition than my 11C.
     
  2. Brad W

    Brad W Cleared for Takeoff

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    My son showed me that while I was helping him with homework a few years back..... it's cheating.
     
  3. Half Fast

    Half Fast Final Approach

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    1984 for me, too. I previously had a TI-58 that took me all the way through college, but it started having key problems. The HP was perfect for me. All the functions and programmability I needed, battery life in years, and it would slip into my pocket.
     
  4. Half Fast

    Half Fast Final Approach

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    You can have the display refurbished. Had mine done a few years back.
     
  5. Capt. Geoffrey Thorpe

    Capt. Geoffrey Thorpe Touchdown! Greaser! PoA Supporter

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    My sliderule works just like new.
     
  6. Half Fast

    Half Fast Final Approach

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    So do all of mine. I think I have about 15 now.
     
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  7. Piperonca

    Piperonca Line Up and Wait PoA Supporter

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    HP-67 got me through college, HP-41 got me a good start in career. Love them both.

    upload_2021-11-30_16-53-2.jpeg
     

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  8. Piperonca

    Piperonca Line Up and Wait PoA Supporter

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    Like that logo. Government issue?
     
  9. Ed Haywood

    Ed Haywood Cleared for Takeoff

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    Got mine in 1984. Standard issue to all USMA cadets. Mint condition; has not been out of case since day I graduated! Still sits on my desk, just in case.

    smaller.jpg
     
  10. Piperonca

    Piperonca Line Up and Wait PoA Supporter

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    Wife has an HP-12 from that time period. Batteries still good. Must last for life...
     
  11. Ghery

    Ghery Touchdown! Greaser!

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    I started out with a TI SR-10 in college. I couldn't afford the $395 that the book store wanted for the HP-35, so I still used my Pickett N4-ES double log slide rule for a trig and log table. I still have both. When I was still working I'd use the slide rule now and then just to harass the "kids". They'd ask what that was and I'd tell them that it was a pocket calculator whose batteries never died and whose display hybrid never crapped out. Both of which have happened to my HP-41CV (see below).

    When I worked for the Navy they bought a HP-25C, but I had to leave it with them when I went to work for Martin Marietta Denver Aerospace. I bought a HP-34C (great calculator) and then a HP-41CV because the HP-34C didn't have enough memory. I still use the HP-41CV to this day. I'll have look around for some batteries as the last time I bought them from Radio Shack and they've gone TU. I've got a number of programs I wrote for the HP-41CV, some of which might even be useful today. "Information Ratio" might not be one of them, however. I'll leave it to the reader to figure out what that was. :p
     
  12. jimhorner

    jimhorner Line Up and Wait

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    Kids? I'll have you know that my HP-11C got me through high school ('1984), my Bs (1987), and my Masters (1989) in EE. Replaced it with a 15C when someone stole my 11C. Still have it, and it still is in great shape, but honestly, pclac does everything I need now. One of the engineers who reports to me recently had his car broken into. Along with a company supplied laptop, he lost his 15C. The laptop can be replaced, but the 15C? Much more difficult.

    Now my son? For some reason he thinks a calculator has to have an equals key. What's the world coming to?
     
    Last edited: Nov 30, 2021
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  13. Pugs

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    '

    Nope - When I went from intermediate in VT-10 (T-34C, T-2B, T-47A) to Advanced in VT-86 (T-47A, TA-4J) in 1988 they didn't give us new nametags for the new squadron, just a new cloisonne logo to stick on it. I peeled it off and stuck it on my calc and there it's been ever since.
     
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  14. Piperonca

    Piperonca Line Up and Wait PoA Supporter

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    Protip: don't leave dead batteries in a HP-41. They will corrode the contacts in the battery compartment making them unusable, maybe unrepairable.
     
  15. Sac Arrow

    Sac Arrow Touchdown! Greaser!

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    My favorite calculator was a fold out graphing HP28S. Unfortunately, it succumbed to a weak case at the battery cover. I bought a 42S to help me get through grad school.

    A borrowed 48X with a survey pack helped me get through the PE exam.
     
  16. Brad W

    Brad W Cleared for Takeoff

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    I went looking for a new calculator some time ago Maybe 8-10 years ago. One of my "must haves" is no equals key. Sure is hard to find now days!
    I ended up buying an HP 35S that I've been using at work sense then, every day. The painted on 1 is already completely rubbed off and the 2 and Enter are not far behind. It's fairly good but you can just tell it's not made as well as the old 11C and 15C series. It's similar though and has one additional function I find handy... "a b/c" key.
    Regardless, I probably don't use 10% of the calc's capability now days and have forgotten so much of what I learned in school. If I had time I wouldn't mind, in a way, auditing a college class or two to get the math brain working again....
     
  17. Tarheelpilot

    Tarheelpilot Final Approach PoA Supporter

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  18. Piperonca

    Piperonca Line Up and Wait PoA Supporter

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  19. Ghery

    Ghery Touchdown! Greaser!

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    Good point. I use my 41CV often enough that this isn't a problem.
     
  20. Half Fast

    Half Fast Final Approach

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    Swap it for an HP-15C. The batteries never die. :)
     
  21. asicer

    asicer Final Approach

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    As opposed to an iPhone?
     
  22. ColoPilot

    ColoPilot Line Up and Wait

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    I have to ask -- why don't the batteries die, is this a joke I'm missing, like it is actually solar powered or uses wall power? The 15c was well before my time so I've never used one.
     
  23. Brad W

    Brad W Cleared for Takeoff

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    they just last a very very long time
     
  24. Piperonca

    Piperonca Line Up and Wait PoA Supporter

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    HP-15C was in my opinion the pinnacle of HP's portable product line. It was the most wonderful balance of durability, usability, and functional completeness ever in a compact shirt pocket scientific/engineering calculator. Plus the batteries last a very very long time. You have to charge an iPhone every fricking day.
     
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  25. Half Fast

    Half Fast Final Approach

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    A set of batteries lasts for years and years. Over the course of a 36 year career as a practicing engineer, I think I only replaced the batteries about 5 times.
     
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  26. Ghery

    Ghery Touchdown! Greaser!

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    Sounds like my HP-41CV. I've replaced the batteries a few times over the last 40 years or so. But, I don't use it anywhere near as much as I used to.
     
  27. Piperonca

    Piperonca Line Up and Wait PoA Supporter

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    Bear in mind that was 40 years ago. PCs weren't in every room, or even every house. If you wanted an app written, the HP programmables were perfect. Not the same use case as the 15C. I started with flight test data reduction in school and fell madly in love with the 67 that saved me from traipsing down to a computer room with Decwriters you had to stand in line to use. Had a collection of swipe cards with routines on them that saved a ton of time. When the 41 came out, I was all over it. Alpha labels meant I could write and share actual user apps with plain language prompts and output. Started writing helicopter performance programs at Bell in the early 80s. Did one for the UH-1 (what I was flying in the Guard at the time) that allowed me to quickly compute max allowable payload for a given flight condition. Army made me a job offer so I became a fed. Good career, thanks in no small part to the HP devices that got it started. Don’t really need the 41 now, but like you, still check the batteries.
     
    Last edited: Dec 5, 2021
  28. Ghery

    Ghery Touchdown! Greaser!

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    I understand what you are saying. Back when I bought the 41CV I wrote a number of programs for it as I had need for them. I remember one time when I was working for Tandem Computers and a wire-to-wire crosstalk program I had written a number of years earlier when I worked for Martin Marietta Denver Aerospace came in handy. If I had been in my office a PC would have been used, but I wasn't in my office and the calculator was in my pocket. I still use a payment calculation program I wrote decades ago now and then, but it is primarily a 4 banger now. Works well, and I have to replace the batteries once a decade or so. :D