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Cake day: June 7th, 2023

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  • Solder is a low melting point metal used to join two metals, where the solder fills the gap and bonds to both metals. This is commonly used in electronics to bond components to the board. For a good solder joint, the solder must be brought up to the proper temperature, and the pads on the PCB (metal 1) and leads of the component (metal 2) need to be heated enough. Additionally, flux is added to the solder to remove oxides on the component leads and PCB pads to allow the solder to bond to the metal; oxides can prevent the solder from sticking.

    A cold solder joint is one that does not reach the proper temperature and/or does not have enough flux, leading to the solder not bonding to the joint, having a scaly/bubbly/matte appearance, and a weaker more brittle joint. Flux also doesnt do as good a job at lower temperatures so it’s important for the joint to get hot enough, and to heat the pads/component leads too





  • That is not how devices like this work; plugging a 5V 3A device into a 5V 1A port means you can only pull 1A. Going beyond that will either trip a fuse on the board or cause the port to shut off, or potentially keep working with diminished voltage.

    If it is USB PD or QC then the devices may negotiate a higher voltage, but for standard hubs like these it’s most likely to just use a USB A port and 5V.

    Eta: a powered hub will also take its power externally from an adapter which can supply much more current, so its draw from the unpowered hub is minimal. In the opposite order, the unpowered hub could max out the current on the powered hub and as long as the port is protected everything should be fine.Theoretically a decent hub would be fused and not allow drawing enough current to damage anything.


  • jjagaimo@lemmy.catoComic Strips@lemmy.world"Future" by Safely Endangered
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    1 year ago

    Afaik this is just fear mongering

    That article cites no sources, and the FDA has retracted requiring warnings for products containing olestra

    According to Wikipedia:

    When removing the olestra warning label, the FDA cited a six-week P&G study of more than 3000 people showing the olestra-eating group experienced only a small increase in bowel movement frequency compared to the control group.The FDA concluded that “subjects eating olestra-containing chips were no more likely to report having had loose stools, abdominal cramps, or any other GI symptom compared to subjects eating an equivalent amount of [potato] chips”

    Source

    Where I originally heard about olestra










  • There are a number of factors involved. Each phone will support a number of protocols and charging speeds, as will the charger. The two devices will typically perform a handshake to negotiate a charging speed before charging begins. This is what allows the voltage to be adjusted, for example to 9/12/24V rather than the 5V default. Then you have to consider the maximum power to be delivered. Some devices might negotiate a higher power, which at the same voltage will result in slower charging.

    Tldr on voltage vs power vs current: power = voltage * current. You want to minimize current in the long wires and connectors/ contacts where there is high resistance because resistance causes power loss, so you use higher voltage until it reaches the end device before dropping it back down.

    If the Android device negotiated 18W and the apple device 25W for example (idk what apple does) then the apple device will charge faster. Also, if the apple device has a smaller battery, it will charge faster. You may be able to get faster charging with a different combination of port/cable, charger, or settings on the Android device. For example, I restrict my phone to charge to at most 85% and slow charge because it keeps the battery from degrading as quickly, so I can still use my phone in several year’s time without having to recharge it every few hours.



  • You don’t seem to understand that you are contradicting yourself. You are thanking Israel who has had a long history of genocide against the Palestinians, and is currently killing numerous Palestinian civilians, and yet you want everyone else to encourage peacefulness…

    Now children have water when they didn’t

    Giving them a basic human right back after taking it away isn’t something to be commended or thanked. It’s something they should never have taken away in the first place and they should be punished for committing war crimes. The Hamas likewise should be punished for their war crimes.