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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




  • It depends on if the problem is recursive or iterative, and how much it needs to be optimized.

    For example, you may use a for loop for a simple find and replace scheme for characters in a string, where you check each character one by one until you find one which matches the target, and then substitute that.

    There are certainly recursive ways to do string replacement in strings which might be faster than an iterative search depending on implementation, but that’s more optimization than I might need 99.9999% of the time

    A recursive problem that’s difficult to solve iteratively is browsing all the files in a folder and it’s subfolders. Each folder may have several subfolders, which you then need to search, but then each of those folders can have subfolders. This problem can be solved fairly easily recursively but not as easily iteratively.

    That’s not to say it can’t be solved that way, but the implementation may be easier to write

    Recursive code, however, is more frequently prone to bugs which causes infinite recursion leading to crashes, as it is not a tool which is often used and requires several more fences to prevent issues. For example, in the folder example, if one were to encounter a shortcut to another folder and implement code to follow that shortcut as if it were a directory as well, then placing a shortcut to a folder within itself might cause the code to recurse infinitely without having a maximum recursion depth and or checking for previously seen folders.





  • 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.







  • 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.