If there's no silicon heaven, then where do all the calculators go?

[alexh]

I can't take a picture of mine right now but I did once, back in the depths of time, before eBay, buy one of each of the Sinclair calculators.

I think there are approx 19 "different" ones.

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[PhilC]

I have the programmable and the scientific Sinclair Cambridge models from the top photo somewhere about, I still use the programable one when I need a calculator.

[rubber_jonnie]

I can't take a picture of mine right now but I did once, back in the depths of time, before eBay, buy one of each of the Sinclair calculators.

I think there are approx 19 "different" ones.

Sinclair_Cambridge_Models.jpgSinclair_Oxford_Calculator_Models.jpg

I have to say, I find the Sinclair calculators to be very stylish, I do like the industrial design a lot.

Nice little collection, do you still have them? Your posts suggests 'yes but they are not so easy to get to'

[rubber_jonnie]

I have the programmable and the scientific Sinclair Cambridge models from the top photo somewhere about, I still use the programable one when I need a calculator.

The oldies are the best

[stephen_usher]

My first calculator, which I fried by attaching the battery the wrong way around in the late 70s, was a Texet 880 "Executive".

Looking on eBay the prices of these are really silly, for what was even in the mid-70s a "budget" calculator.

Note: The battery is a PP3, 9V one but the battery bay requires you to press fit the battery in without and polarity restriction. Stupid.

[DoG]

I found my fathers old calculator. It's a SHARP EL-805. Google it and found that is the first calculator with LCD. Most of display still work. I don't know if one could get the numbers working again somehow.

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[rubber_jonnie]

I found my fathers old calculator. It's a SHARP EL-805. Google it and found that is the first calculator with LCD. Most of display still work. I don't know if one could get the numbers working again somehow.


front_smol.jpg
display_smol.jpg
back.jpg

Very neat. I think the trouble with older LCDs is they are difficult to repair. My brother gave me a Sharp handheld computer and the display only worked in a couple of spots, just enough to know it worked.

I was able to get a replacement LCD from the US, but it wasn't cheap and was difficult to fit. The point being that for custom stuff it's not always so easy.

I did repair the LCD on one of my Wonderswan consoles, but that was down to the polarising film going bad, and it was possible to replace just that.

[rubber_jonnie]

So I pulled it apart and it's a fairly simple single IC model with a few discrete components:

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The button matrix seems fairly simple with 4 connectors across and 5 vertically, so checking the necessary pins showed the decimal point button to be working.

What weren't working were the two electrolytic capacitors which were reading low and had turned into a resistor respectively. I'll fit some new ones later.