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Joined 3 years ago
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Cake day: June 12th, 2023

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  • Carbon-14 dating only works back to about 50,000 years, most fossils are older than that and they use radiometric dating.

    (Not a scientist, I’m sure my wording will make experts cringe, but I think my gist is good)

    Fossils are basically rocks that form around hard things like bones. They look at radioactive elements in the rock and figure out how much has decayed and they know when the rock was formed.

    Uranium lead dating is one of the most used methods. In it, they look at zircon crystals and measure the amount of uranium and lead. Uranium decays into lead, so that tells them how long the decay has been happening.

    That always seemed sketchy to me, how do they know it didn’t just have a bunch of lead in it to start with? Then I learned something…

    When zircon forms, lead can’t bind with it and it gets pushed out of the zircon. Uranium doesn’t get pushed out, so there are small pockets of uranium in fresh zircon and no lead. A million years later, we just look at how much lead and uranium there is and get a very good idea at when it was formed.


  • Slate has stated that they will not have a cellular or other type of connection. It does need some type of connection to do software updates, and that will be from your phone using their app to the truck via USB.

    They’ve also stated they won’t track your driving data. You can opt in to share data about the truck’s health through the app for servicing purposes, but that’s all. They’ve also promised not to sell any kind of data to third parties.

    That could always change, but I’m on the wait list for one and there are people on the slate forums who are serious about privacy and are watching this and seem pretty happy for now.






  • Don’t worry so much about gain, for your sanity. When buying antennas, it’s usually just a number they made up. Gain is a measure of the directivity of the antenna’s radiation pattern, so a 10DBi gain antenna would be very different antenna like a Yagi antenna that has to be pointed directly at a another radio to work.

    The advice about 1/4 wave antennas is good. Antennas need to be a fraction of the wavelength of whatever frequency they operate on. 1/4 wave is sort of the standard antenna that always works well. I prefer 1/2 waves myself, the radiation pattern is not all that different but a little better in the horizontal and they work better without a ground plane.

    1/4 wave for 868MHz is around 3in or 7.6cm and 1/2 wave is around 6in or 15.2cm. So, basically, any antenna around 3 or 6in or 7.6 and 15.2cm should give you the best performance in antennas of this style and size. The giznot is 17cm, which I assume is a 1/2 wave plus the base.

    When it comes to Meshtastic, I’d say the longer antenna will be better, but if you want to put your device in your pocket or something, a shorter one will be fine too. The good thing is, the antennas are pretty cheap. If you get the Giznot you can also get a 3 inch antenna for like $3 and use them both.












  • That’s how they make paper and a lot of other flat goods like tape. The manufacturer makes these gigantic rolls then there’s this entire industry called converting where a company, a converter, takes it and process it down into a finished product. They may add adhesives, lamination or printing to it during the process.

    You can go to a store and buy 3M tape but 3M doesn’t actually make it like that. They make a 12ft wide, 10,000 ft roll that someone buys and forklifts into a machine that cuts it into a bunch of smaller rolls that you can buy