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Battery-free Game Boy (2020)

freethegameboy.info

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Re: Battery-free Game Boy (2020)

#71

Post by c12 »

mike256 wrote: post #42
pfannkuchen wrote: post #13

Earlier quoted context omitted.

I think the poster wants this to work without the “you hold it near a thing” part.

But it still works almost the same way. You hold it near a thing to get energy is mostly required because it works with very little power, let's say some milliwatts. Whereas old AM stations where sending in the range of megawatts.

That broadcast power is required to provide range. Radio waves obey the inverse-square law: for every doubling of the distance from source you get four times less power. This is also why wireless power transmission at a distance isn't really viable.

Re: Battery-free Game Boy (2020)

#73

Post by flockonus »

alex_duf wrote: post #53
0_____0 wrote: post #32

Earlier quoted context omitted.

I've heard of AM radio being audible in non-electric structures, like an old hangar door. Some combination of geometry, metal surface condition (corrosion?), and proximity to a station.

There's an anecdote of someone hearing voices, but it turned out to be AM radio. They found out it was the metal in two cavity filling that made the teeth vibrate and transmitted sound to their ear. Not sure if it's just an urban legend or legit, but I like that story.

Seems accurate: https://www.quora.com/Is-it-possible-to-hear-radio-stations-...

Re: Battery-free Game Boy (2020)

#74

Post by dizhn »

ddevault wrote: post #70
IshKebab wrote: post #49

Earlier quoted context omitted.

Am I the only one that thinks this is a normal level of comments? Ok maybe slightly more than I would normally do... But if I was reading it my thought would be "thank god they wrote comments" not "they commented the heck out of this!"

From the perspective of someone who generally writes far fewer comments than this, I find that this code has a number of comments which is well-justified due to the complexity of the subject, poor availability of external documentation describing the interface it implements, and the nature of the code. However, the code can be written in a manner which is still readable with fewer comments. Here's a sample from the f…

I like the changes but I think the original has merit too. Along with the comments it is documenting the parameters/bounds that apply to this device where they are actually being used, making the code a kind of documentation for others who want to implement similar things. Having these defined in constants elsewhere would require some back and forth if this "document" is used as a reference.

Re: Battery-free Game Boy (2020)

#75

Post by ddevault »

dizhn wrote: post #74
ddevault wrote: post #70

Earlier quoted context omitted.

From the perspective of someone who generally writes far fewer comments than this, I find that this code has a number of comments which is well-justified due to the complexity of the subject, poor availability of external documentation describing the interface it implements, and the nature of the code. However, the code can be written in a manner which is still readable with fewer comments. Here's a sample from the f…

I like the changes but I think the original has merit too. Along with the comments it is documenting the parameters/bounds that apply to this device where they are actually being used, making the code a kind of documentation for others who want to implement similar things. Having these defined in constants elsewhere would require some back and forth if this "document" is used as a reference.

Well, I said upfront that the level of comments here is fine. Just offering a perspective on how it could still be good code with less. In general I think it's fine to expect a reading of the code to be paired with a reading of the documentation/specification; in the absence of such a resource for the GameBoy the comments here are well-justified. I would definitely add more constants, though, and I would anticipate that a second implementation which references this would start by re-defining all of the constants in its own code.

Re: Battery-free Game Boy (2020)

#77

Post by Dalewyn »

HideousKojima wrote: post #36
0_____0 wrote: post #32

Earlier quoted context omitted.

I've heard of AM radio being audible in non-electric structures, like an old hangar door. Some combination of geometry, metal surface condition (corrosion?), and proximity to a station.

Poorly shielded wires and speakers can pick up stations as well. My brother's cheap guitar amp would randomly pick up garbled bits of sound from radio stations (while not plugged into any power source)

>Poorly shielded wires

That's literally an antenna[1][2], actually.

[1]: https://en.wikipedia.org/wiki/Monopole_antenna

[2]: https://en.wikipedia.org/wiki/Whip_antenna

Re: Battery-free Game Boy (2020)

#78

Post by logicallee »

This is an incredibly important project under the new reality that Russia can cause war and havoc at any time and in any state. If they can do it in a Europe that has basically been at peace for 70 years, and facing massive worldwide opposition and direct opposition from the United States in the form of aid, weapons, and people, then they can do it anywhere, even in the continental United States. No place is safe under such conditions. In Ukraine as a war crime, Russia targeted energy infrastructure including power plants, bringing energy grids offline.

This is something that could deprive people of basic communications and information access.

The mitigation of this seems difficult. Solar panels on the outside of houses can be destroyed by bombing easily, and gasoline powered generators on the inside are loud, expensive, and require ventilation for safety.

How can a people stay connected and continue to communicate under active Russian attacks on their energy grid?

With these thoughts in mind, when I saw this project I smiled, because it approaches the issue from an alternative angle. Who needs a loud and potentially noxious gasoline generator if it is possible to reduce the display draw to an amount that can be successfully powered from incident light?

Such a solution can solve pressing issues in our time and going forward. Quiet, compact, and mobile.

A good solution for the worst possible world.

Re: Battery-free Game Boy (2020)

#79

Post by javier_cardona »

Getting the electronics to work on such a tight energy budget is a big challenge, very impressive! I've worked on a similar concept using a bistable display and a supercap for energy storage to recharge very quickly when sun is available. This is for more zen-like use cases, like chess puzzles: https://lightnote.cardonabits.com/products/lightnote-chess-e...

Re: Battery-free Game Boy (2020)

#80

Post by Schroedingersat »

atahanacar wrote: post #21
StrangeATractor wrote: post #17

Earlier quoted context omitted.

I heard a tale in the days of yore where a radio station was not getting the range promised by the laws of physics. When they did some investigating they found an engineer that lived next door to the tower was syphoning power from the radio waves as part of a home experiment. I'm not qualified to determine the plausibility of this, but I hope it's true.

Can you siphon power from the sun so other people can't get its radiation, without you covering the entire surface with something like a Dyson sphere?

If your object is roughly the size of a wavelength or less, it can siphon off power that would be a few wavelengths away.

So a bacterium might be able to annoy their neighbor. But that's about it.

If the sun was in some kind of equilibrium with stuff around it (ie. There was a big mirror acting kinda analogously to a ground plane) you could effectively cast a shadow much bigger than yourself.

But that's about it. Visible light is very small.

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