Author Topic: Calculators  (Read 4375 times)

Antraciet

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Calculators
« on: January 09, 2013, 12:00:13 PM »
When i saw Martin's video on his other blog : http://www.youtube.com/watch?v=cAAUS6JB-YM , I took my old calculator from under the dust; An MBO Alpha 7000 'liquid crystal'.
For years i didn't used it. Put some batteris in it (button batteris for watches, or how you call them).
First the calculator didn't worked properly; half of the numbers, a calculation wasn't possible. Then i just left it on, and after 15 minutes, the display starts to works, calculate something is possible again.

Someone has a explenation for that ? I thought electronics works or not, this isn't an old engine  :D
just curious.

some pics in the attachments. I used it in the '80-ties.

SeanB

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Re: Calculators
« Reply #1 on: January 09, 2013, 02:37:40 PM »
Capacitors used internally by the chip went leaky with disuse, but reformed with time under power so the chip oscillators could work again.

Antraciet

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Re: Calculators
« Reply #2 on: January 16, 2013, 08:54:57 AM »
Capacitors used internally by the chip went leaky with disuse, but reformed with time under power so the chip oscillators could work again.
Thank you. Only a few buttons are not working, the x and the square root, those i need the most. Maybe dust or so in it, don't know.
Ach well, time for buy a newer one.

MJLorton

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Re: Calculators
« Reply #3 on: January 16, 2013, 03:11:27 PM »
Thanks for the post Antraciet...my brother had one of those in the 80's...I had forgotten about it till seeing the picture.
Play, discover, learn and enjoy! (and don't be scared to make mistakes along the way!)

SeanB

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Re: Calculators
« Reply #4 on: January 16, 2013, 03:34:58 PM »
I dug out my old Casio FX602P, popped in new CR2032 cells and it powered on and works fine. I have had that one since I was in school.

orbiter8

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Re: Calculators
« Reply #5 on: January 16, 2013, 03:46:54 PM »
Thank you. Only a few buttons are not working, the x and the square root, those i need the most. Maybe dust or so in it, don't know.
Ach well, time for buy a newer one.

If you've not yet bought a new calculator, may I recommend the Casio FX-991ES PLUS. It's an awesome calculator, especially for the price. In fact so good I bought two of them :)

SeanB

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Re: Calculators
« Reply #6 on: January 16, 2013, 04:19:43 PM »
Not quite a calculator but still cool.

Touch and tell from TI, made in 1982 or so. Tried to power it but no go, will try again with different batteries again some time soon.

Also some die shots of old chips I have uncapped ( ceramic packages) along with the optical block from an old inkjet printer. Last is a sensor from another inkjet. This one is interesting in that it uses a steel rod and has a magnetic pattern apparently set into the rod, as it reads the printhead position magnetically.