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Joined 2 years ago
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Cake day: August 4th, 2023

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  • Start by defining your available power. How many watt-hours can you generate? A small 100W solar panel can provide an average of 400Wh of energy per day in the winter. That’s more than enough to run a 10-inch tablet 24/7 and LED lighting at night. I’ve seen 360W solar panels for under $100 on the used market. That’s a couple of KWh a day. Even a 100W bicycle generator and a 30 minute workout would power a tablet for 8 hours.

    If power consumption is that big of a factor, perhaps separate devices for video, music, and reading would be beneficial. A dedicated music player can consume less than a watt. An e-paper reader requires fractions of a watt.

    I have a folding 100W panel, a 30Ah 12V LiFePO4 battery, and a charge controller that I use while car camping. It keeps all the electronics running for a group of 4 without relying on a noisy generator. The battery is big enough to compensate for a couple of rainy days.

    My backpacking setup is a 15W panel and a 30Wh battery. That kept my phone and flashlight charged for 2 weeks on the Pacific Crest Trail.





  • I don’t think most people realize how dependent we are on undocumented workers. Wait until it becomes illegal to hire them and INS roundups start again. Then the carwash price goes up, the daycare closes, or the landscaper goes missing. Maybe the snow doesn’t get plowed or the restaurant prices go up because they can’t find cheap kitchen help. Construction-related companies will be decimated, and the cost of home repairs/remodeling will skyrocket. In my area, electric rates will increase because half of the crews that keep the vegetation trimmed back from the power lines are undocumented.

    They’ll come for the employed undocumented workers first, because they can make it illegal to hire them, just like it used to be 50 years ago. No green card, no work.





  • We won’t have a clear winner. No matter which candidate “wins”, there will be widespread allegations of voter fraud. There will be protests. Biden will declare a national emergency. What happens after that? I don’t know. But I am prepared for major social unrest.

    A large number of people from both major parties are absolutely unwilling to accept a win by the opposing candidate. I’ve never seen the country so divided.




  • There are plenty of companies that will sell your name, email addresses, phone numbers, street addresses, marital status, and relative’s names. They obtain the information from publicly sold databases. I had access to one that had all that, plus the registration info for the car I drive, my estimated income, my military record, my driving record, my political party preference, and pictures of my home that had been on the realtor’s website.

    The scary one was when a phone center employee in the Philippines stole my wife’s debit card number and then did two big Western Union MoneyGram transfers to a couple of Filipino men. That means bad actors have access to the credit companies’ databases from which Western Union draws their proof of identity questions, like who holds your mortgage, where you lived when you were 10, and the make/model of your first vehicle.

    If you’re well-off enough to be a financial fraud target, paying a company for identity theft protection is probably well worth it. Put fraud alerts in with all the major credit bureaus too. That usually stops identity thieves from accessing your credit. If you use 2FA with your phone, make sure your telecom provider will not transfer your number to a new device without in-person authorization and authentication.









  • If you place a tea bag in a cup of water at 20C in a thermally isolated vacuum chamber, when the chamber pressure is reduced to or below the vapor pressure of water at 20C (about 17 torr, or 1/3 psi), it will begin to boil. The vapor produced will be at 20C and the water in the cup will be 20C and begin to decrease, because of latent heat of vaporization needed for the liquid/gas phase change. The water will continue to boil as long as the pressure is maintained at or below the vapor pressure of water at that temperature. Eventually, the water reaches 0C. Then it will stop boiling and begin to freeze as the latent heat of fusion provides the necessary heat to continue evaporation. When all the water has converted to ice, the vapor pressure is greatly reduced. The ice will sublime (go from solid to gas) still, but as that continues to cool the ice, the vapor pressure also drops. As the temperature drops, sublimation will slow until it is nearly zero. So you would end up with a tea bag encased in ice.

    In your example, if you suddenly exposed to the cup and tea bag to the vacuum of space by rapidly venting the air, the water would explosively evaporate, shredding the tea bag. You’d be left with bits of tea leaves, an empty cup, and a lot of very fine ice crystals.