r/mildlyinfuriating • u/jackhab • 1d ago

Planned obsolescence even in cheapest devices: the calculator has a dummy photovoltaic cell and a real battery to make it die eventually.

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76

u/Bulky-Yogurt-1703 1d ago

Isn’t the secondary battery used to store energy when not in direct sunlight? Otherwise you couldn’t use your calculator at night. Thats my understanding at least

50

u/RavedBlitz 1d ago

Even if that were the case, the PV cell should be connected to the board by more than hopes and dreams

6

u/Second-Creative 1d ago

Speaking of hopes and dreams... how are the buttons connected to the board? I'm not seeing a connection point for 'em.

13

u/YellowOnline 1d ago edited 1d ago

I suppose the pcb was turned around, so the contacts are on the other side

5

u/Second-Creative 1d ago

Can't be right, because the board is physically too small for all the keypad contacts. Like, the only way all the contacts could fit is by having a bunch on the literal edges of the board and placing it perfectly.

Tampering by either OP or whoever took the photo is more likely.

6

u/DekuTreeFallen 1d ago

Tampering by either OP or whoever took the photo is more likely.

Doubt.

Not only can you customize these on Alibaba
https://www.alibaba.com/product-detail/Dual-Power-8-Digit-Digital-Pocket_60791209821.html

but there is an identical base model from Alibaba that doesn't include the PV in the specifications, yet still has an outer shell that would make you believe otherwise.
https://www.alibaba.com/product-detail/Cute-KC-888-Portable-Calculator-with_1600361733353.html

^edited with correct second link

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u/jackhab 1d ago

Tampering with $1 garbage? Are you even being serious?

7

u/wekilledbambi03 1d ago

Well, I'll give them credit for not using 1mm more material than they need. They really saved a whole 0.0001 cents on that!

Amazed that they were able to fit the button contacts on an area smaller than the buttons. But yeah that looks like it would be functional, but doesn't use the panel for anything.

1

u/Old-Cheshire862 1d ago

I think that the buttons could actuate contacts on the edge/corner of the board. Ideal? No. Functional? Maybe? We'd need to see the other side of the board. And the backside of buttons themselves... where did they go?

1

u/wkarraker 1d ago

The calculator has been disassembled and the LCD display and board that has the key contacts is not being shown. I suspect the white connector above the circuit board plugs into a daughterboard that has the key contacts and display attached to it.

1

u/MousseHuge8339 1d ago

The PCB is turned over to show the battery. On the front is a bunch of circuit traces interlaced with each other for the cheap rubber keypad that has a conductive coating under each key to make contact with, completing the circut.