Panasonic 805 Calculator

[der Mouse]

>> Are you sure it's a LED display?  That sounds more like behavior I
>> would expect of a vacuum fluorescent display.  If an LED really is
>> doing that, the problem is with the electronics, not the diplay.

> I can't be sure. I didn't think it was an LED (the unit is from
> around 1970 or so), but when I looked at it a little while ago, it
> looked kind of like LED segments behind the plastic lens.

> They glow a bluish green if that is any help.

That is almost certainly vacuum fluorescent.  There are a lot of such
displays that use the same kind of seven-segment number formation you
commonly see with LEDs.

There may exist, today, LEDs that produce blue-green light.  I'm fairly
sure there weren't any in mass-market consumer electronics (even fairly
specialized devices) back around 1970 - quite likely not any at all
back then.

Not that that helps much with your question, since I am not competent
to comment on fixing either kind of display.  But it may help to know
what you're dealing with.

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