Operation and bypass diode design

[jayk]

Good beh super, thank you for your advice, it's better in my little head!

Sorry for the abbreviations Izentrop:
- by Voc I mean open circuit voltage or no-load voltage, when the panel is not connected
- by Vmpp I mean voltage maximum power
I arrive a little late

[Gaston]

I have a solar calculator that is over forty years old

Let me doubt

The first calculators appeared in 1971, they were equipped with LED screens which consumed far too much to be powered by solar cells.

LCD screens appeared commercially in 1979 and one of the first calculators with solar cells fairly quickly thereafter..

Your machine is probably not more than 37 years old

[Obamot]

ok, go for over 30 years

[Obamot]

... there it is, SL 672 in sub-brand.

image.jpeg (39.88 KB) Viewed times 3522

similar model than this one, from 1981 (SL 1002) with more functions

as I think the second has more functions, and according to the numbering of the models I would say that mine was bought 1 or 2 years before (and soon after available at Technico-Taiwan)

Maybe 36 or 37 years old ... I was not that far away

[Gaston]

... there it is, SL 672 in sub-brand.

According Calcusium, it would be from 1981 or 1982 according to epocalc, either 34 or 35 years old.
It's not bad already, but still not "over 40"

[Obamot]

well, I'm not on horseback on that, but if you notice the solar panels, those of the M-Office are of a techno which seems appreciably older than that of the Technico, however it is excluded that it have "over forty years", indeed, I will have to wait a little longer and / or that I ask for an extension of the guarantee ( )

So yes, okay with 1981-1982, how many will I put for you? Mine is a little dented, I'll give you a good price, they are "collectors" (they don't even sell for US $ 5.— on e-bay mwouahahahah!) But it still works!

proof that even in planned obsolescence there can be failures

[Ahmed]

proof that even in planned obsolescence there can be failures

It makes sense to first develop a novelty before being able to degrade its quality in a controlled manner ...
My first calculator is a Tandy and it still works just as well; she must be in the same ages?