What could stop several electronic calculators working?

[Nick]

I have three electronic desktop calculators. All battery powered with some sort of solar input as well. All are less than five years old. One is Sharp, one is Casio & can't remember the name of the third. All have had the button cells (CR2032) replaced within the last twelvemonth and all working fine. None of them are overused. I try to remember my maths, but struggle with long division! This Monday the one in my office didn't want to play, display mostly not working, displaying gibberish. No problem thinks I and gets the one from my workshop. Worked fine for about ten minutes then exactly the same symptoms. That evening I used the calculator at home for some while and it was spot on. Took it to the office in the morning and within ten minutes it packed up with exactly the same symptoms as the previous pair. I have since moved all from the office and put new button cells in each. All appear to be u/s. I don't live on top of, or near, a nuclear waste site but this seems a bit too much for a coincidence.

Nick.

[cynic]

leaky microwave oven?

[OG]

What exactly were you calculating? There was a documentary on TV that had something similar a couple of weeks ago. I think it was called 'Spooks' or something.

[Ron Lowe]

EMP?

[pete]

damp? insects? static (air too dry)? murphy? recently expired warranty? all batteries installed at the same time, so leak away to zero after the same period?

If the display becomes "gibberish", it might be the contacts between the display and the calculator circuit board. From the one's I've dissected (purely for scientific reasons, of course) the cheaper ones seem to have some sort of conductive rubber contacts on the display and this is simply held in more or less contact with the copper (no gold plating here m'boy) contacts on the calculator's main board. I doubt if it would take much in the way of oxidation or dampness to form a non-conductive corrosion on the copper and stop some of the contacts from contacting. If you feel so inclined, take one apart and give all the circuit board contact points (to the display and the keys) a good rub down with a piece of normal, unused printer/copier paper. it's slightly abrasive and may just shift any contamination off the contacts.

p.s. I have a PC that goes through phases of craching/locking. There is one particular SIM where this "cure" brings it back t life - of course it could simply be the mechanical pressure from removing it and replacing it in the socket.

[tony sayer]

Nope .. EMC got any wireless or radio equipment on the go nearby?...

[Ron Lowe]

I was not serious about the EMP.. I didn't notice any news about a nuke going off today.

But aside... since you're not the OP, how are you in a position to deny EMP anyway?

Malicious calculator-hating old-school maths teacher with a home-made focussed EMP blaster?

[Tabby]

Odd multiple office equipment failures are usually down to a young enmployee abusing it. Probably not this time though.

NT

[Gib Bogle]

Static electricity?

[tony sayer]

In article , Ron Lowe scribeth thus

Suppose if there was we'd all be off-line now;!...

You prove it first ;)..

Who moi;?..

[john hamilton]

=========================================================================

Aliens can cause interference with electronic equipment.

[tony sayer]

In article , john hamilton scribeth thus

Yes of course, silly me for not thinking that.

Any idea where there're from, somewhere nice I hope;?..

[Adrian C]

The human body can hold and produce a lot of static charge that can interrupt the normal operation of electronics, but for three devices to almost immediately go phut would mean this fellow has the biological properties of a very large capacitor, kind of 'catfish' in capacity. Probably a good idea for him to keep a safe distance away from flammable gases and vapors.

[Dave W]

carpet and the particular shoes the OP was wearing.

In my old work in electronics, a salesman was demonstrating his electrostatic meter and asked me to slide my feet along the floor to get myself charged up. It didn't work because I was wearing shoes with unusual soles made of the same type of plastic as the floor tiles.

Incidentally I wish I could find shoes like them now, because the grey soles remained flexible for their whole life, not like the common black material that splits right across, or wears down by 5mm exposing vast cavities for built-in obsolescence purposes.

Dave W

[Spamlet]

Anything changed or been moved in your office? New external hard drive (Big magnets); router; powerful mobile phone (regular pips from these); new mouse mat or keyboard; graphics tablet; radio clock; new polish or cover on desk; new office cleaner; new office suit or other clothing; office cat; something switched on in desk drawer; new phone/power lines outside; cfls on the blink; dimmer switch on the blink; suspicious unmarked van parked outside... Some other freakish thing (I notice BBC4 is pixcelating quite a bit on our cable lately. Similar thing happened a year or two back: never found out why.)

Call for Mr Holmes I think!

S

[Gib Bogle]

They prefer to call it "air cushions".