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About Callipygous

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  • Birthday 02/05/1987

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  • Location
    Livermore CA
  • Interests
    wakeboarding, snowboarding, video games.
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    none at the moment
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  1. I mostly agree with your math. The part I wonder about is whether the batteries have a fixed output, or a recommended maximum output. What I do know is that the project has worked successfully for reasonable periods of time. The latch is activated for 2 seconds at a time. I don't know if that qualifies as a sustained load, or if they really mean "don't draw that much for 2 hours" The link from my original order no longer works, but the latch is basically identical to this. That claims a draw of .43 amps, which is more than your calculation says my batteries should be okay with. So again, I don
  2. I have been trying to figure this out. It looks like there are some options that are basically what I'm using, which is variable input, adjustable output in the ~3-30v range. Then there are some other ones that seem like they might be easier to use and more reliable, because they aren't adjustable, they just put out 12v. So far I haven't figured out how to consistently find and filter those. This is the closest I have found so far. The downside is they talk about current more like 50mA, not the 1-2 amps I think my latch probably needs. You have any hints for how to specify the non
  3. no desire to complicate things, just lack the experience to know about that and the vocabulary to find it.
  4. I made a project involving voice recognition on a raspberry pi so you can speak a password to open a box. Long story short, my DC-DC step up converter to power the latch seems to be super unreliable. I am wondering if some of my trouble is related to how I have it wired up and if someone could suggest a better approach. I have 2 battery packs (https://www.adafruit.com/product/354) wired in parallel. Those are powered off a charger (https://www.adafruit.com/product/390) So output of this board, and the two batteries, are connected to the main positive and negative lines at the edge of
  5. I find that depends. If I extend my arm all the way up my shoulder socket pokes out, effectively changing my armpit from concave to convex. Just another complication for the experiment.
  6. My understanding is that yes, it would work with wood, but not as well. Something about the magnetic inductance or capacitance or some such of the material? I am not sure what you are offering with "a derivation of it" but yes please, whatever explanation you can offer of any concepts I'm missing.
  7. I am going to attempt to put this in laymen's terms to the best of my understanding, and probably butcher it in the process. I look forward to your corrections. We have a few carefully arranged coils of wire known as the stator. We are going to apply a voltage to it, which is going to cause current to flow. Current flowing through a conductor generates a magnetic field. Because of the nature of three phase AC power, and how we've arranged our coils, our magnetic field is rotating in a circle at 3600 RPM (dependent on who's electrical standard you are using and how you've set up your coils
  8. I have met them, but as I mentioned earlier, it has been a very long time since I have had to do anything with them. That part is throwing me off. My (limited) understanding of circuits includes a rule that in a circuit with no branches, voltage can vary from point to point, but current is the same throughout. If they are wired in series, how can they have different currents? My understanding of slip is when there is enough load on the rotor that the force exerted by the magnetic field is not strong enough to spin the rotor at the same rotational speed as the
  9. Thanks for the replies. I would be interested to hear more about the relationship between impedance and and slip. It seems like this is basically the same thing as in rush current, which I understand as far as what it does, but not so much the nuts and bolts of why and how. John, your comments on back emf were helpful, just knowing some better keywords to search yields better results than I was getting before. But I was wondering, if the lower RPM is the result of lower line voltage, then it seems like the lower emf produced wouldn't be that much of a difference. Both line voltag
  10. I have come to accept that when an induction motor receives lower voltage than it was designed for it will pull higher current. This doesn't make any sense to me, but I have seen it stated enough times that I'm willing to believe it. Everywhere I look provides total nonsense explanations. They say things like "the motor will draw more current in an attempt to maintain its torque" as though the motor has agency and chooses how much current it draws, or "in order to provide the same power" as though the motor cares how much power it provides. The version that would make sense to me is you h
  11. Migl, that is easily countered. Just ask the person posing such a question to provide a definition of "biological traits of a man/woman" that works in all cases.
  12. 1. Expose them to the fact that someone disagrees with them. People with those kinds of beliefs have often spent most of their lives surrounded by people who unquestioningly think the same. 2. Abandon all hope that you can actually alter their belief, because that's what it is: a belief, not a hypothesis. 3. Focus on exposing people who are not yet entrenched to a variety of perspectives. This guy probably wont be convinced, he may gradually find himself in a less aggressive stance, or may not. Hope for his children remains.
  13. Yeah, I can see the benefits of that approach. Maybe im wrong, but I feel like my circumstances have some additional hurdles. The organized group effort sounds good for a city park, but im dealing with more of a wooded area out in the hills. I feel like one (particularly me) would have a hard time coordinating a group to go out there, trek through poison oak, and gather trash in hard to reach, off-trail locations. Especially without trampling a lot of flora. The supervisor I report to knows that I've been hauling tires out with a backpack for the better part of 2 years and has yet to say
  14. My favorite local park is unfortunately place below a road, which has turned it into a dumping ground. I have spent a considerable amount of time, money, and effort removing as much of the trash as I can, but the process raises some questions about which items are worth the effort. Some items seem like they have a pretty low impact other than being an eyesore, like glass. other items require a disproportionate effort due to size, weight, and location. The park service has told me that some of them are not worth removing because the impact of digging them out, and erosion in hauling them o
  15. It sure is. I believe that should be an H. Thanks! You were able to decode it with just the first one?
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