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greenhorn

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Everything posted by greenhorn

  1. A few things about those UV tubes: I have very similar LED tubes that I bought at a regular shop here in Austria. It's very likely that they are sourced from the same company in China. My version even runs on 220 V, so I guess it's more "fun". Those power cords that you got (connector on one end, stripped wires on the other) also came with the tubes I bought. Those are needed if you want to hard-wire those tubes somehow. If you want to daisy chain several tubes together, there are specific connector cables with plugs on both ends. There are also end caps that should have come with the tubes you bought to cover the otherwise exposed mains voltage pins at the other side of the tube. What's also interesting is that the tubes in the video don't have any earth connection even though the connector could support it. My version does have a working earth connection.
  2. greenhorn

    The Swiss Health Ministry has dropped basically…

    I wish you all the best for your booster injection. Getting the certificate for it makes sense, you never know where you will need to show one in the future. Do you have to apply separately for the certificate? Here in Austria, we automatically get one that we can retrieve from the national vaccination database. It is in both German and English and contains an EU compliant QR code. I always find it interesting to hear about how those things work in other countries. It made me realise that I am quite lucky here, since for example I can basically do as many PCR tests as I want for free: we can get test kits for free, do the test at home while filming ourselves, put everything in the box the stuff came with, bring that box to a local supermarket (from where it is collected twice a day and sent to the lab). We then get the results per mail (usually within 24h) including an official certificate with a QR code. I was quite surprised to hear that for example in Germany people have to pay for PCR tests unless they fulfill certain criteria (such as having a positive rapid test). Some people even found out that it might be cheaper to fly from e.g. Berlin to Vienna, get PCR tested there and fly back than to get a PCR test in Berlin, which is mind-blowing.
  3. I had another look at this and found this article from 2020 link . If I understood that correctly, even by then, this researcher who seems to have invented this concept talks about replacing the insulator needed in transistors with a specially processed cellulose-based material. Since traditionally this insulator needs silicon (consists of SiO2 if I remember correctly), replacing it with this new material saves ressources (silicon) and avoids the creation of nasty by-products of the production process. One of these by-products is sulfur hexafluoride (SF6), which is one of the most potent greenhouse gasses. As far as I know, if you should require SF6 in a lab, the mandatory containment procedures are quite extensive. In this article, it is also mentioned that those "paper transistors" are not likely to replace conventional transistors in any high-performance devices soon. I don't think those transistors could have that much power because of the generated heat. This would also mean that they will not be able to sustain high clock speeds, since those require fast switching which in turn is responsible for the power consumption and generates the heat. Of course there are still many applications for this technology. If those transistors are truly bio-degradeable as claimed, then it could reduce the environmental impact of all those low-power consumer devices that don't need too much computational power. I also wonder how these devices handle changing environmental factors, especially humidity. I have seen many interesting ideas presented by scientists over the years, but so many turned out not to be practical, which is totally normal. For every breakthrough there are tons of failures, but that's how we learn and continuously improve.
  4. I know, just an expression. I am aware that it is usually a capacitor or capacitor bank in most cases. I have also seen such a thing in combination with LC filters on one PCB.
  5. Since you will know the data of your more power-hungry devices, you can look at their rated power and derive their current draw. Also keep in mind that some devices can have very large inrush currents (which sometimes can trip a breaker, so make sure the proper type of breaker is installed). What you could do is to ask the electrician to install current monitors for each phase so you know how close you are to overloading a phase. Depending on the needed current rating, there should be resettable circuit breakers available. This makes sure that the downtime is minimized in case a breaker trips. I'm not sure how far "up" the resettable ones get in terms of nominal current.
  6. In theory, this is possible, but not worth it (due to cost and power losses). You also have to take into account that those devices usually need a lot of power, which means that a single phase circuit would need to handle a lot of current. If you have to rewire everything, keep in mind that there might be several ways of doing that depending on what the electrical code in your country specifies. Since this is a workshop, you could think about installing wall-mounted or ceiling-mounted conduits for the wires, which should be easier and less expensive than running everything inside the walls.
  7. Ok, that is quite a large setup. I think the best thing would be to get an electrician who then designs the layout of your electrical system and also determines what kind of connection you need from your energy supplier. Given the type and amount of devices you have/want to have, 3 phase power definitively makes sense from a physics point of view and is probably even mandatory for the expected power draw. One thing to consider will also be which devices will/can be active at the same time, because that influences the peak power consumption the system has to be designed for.
  8. As @suedseefruchtalready said, load balancing can be done, but this only really makes sense at a much larger scale. At a home/small company/workshop level, the "balancing" is usually done in a static way by the electrician who should determine which single-phase circuit to attach to which phase so that it becomes less likely that one will blow the fuse of a single phase while still drawing reasonable amounts of current/power. You will also find that more power-hungry devices tend to need a 3-phase connection themselves. In that case, you can hope the device's manufacturer has done some internal balancing inside of that device. Since you are talking about kVAr, I am wondering if the thing you are actually more concerned about is the power factor. Devices with a bad power factor can be a problem (usually from the workshop-level of power consumption upwards), but in many cases the device manufacturer uses a power factor correction mechanism to minimize that problem. It would be helpful if you could describe your setup a bit more (number and type of device, current/voltage rating, power factor, type of mains supply with max allowed current draw per phase) in order for us to figure out what advice we can give you.
  9. Well, I am an electrical engineer and I can confirm what other people have already told you in this thread: You seem to have several misconceptions about the fundamentals of electromagnetism. That's not a personal attack, just an objective evaluation of your claims. If you want to contribute to the development of technologies like the ones you are describing, you first need to understand the underlying concepts properly and then have a go at it. Beware of those youtube videos with permanent magnets and some amount of wire around them. Several of them are actually fake. You can even try building such contraptions yourself. Magnets are not that difficult to get (just follow the appropriate safety measures if you get a very powerful magnet), copper wire is even easier to find. Then, you just need a cheap multimeter (either you have one, can get a cheap one or maybe borrow one) and some sort of load like a small resistor and see if you get any power output. Just keep that circuit away from other large electromagnetic fields so as to not compromise your results.
  10. greenhorn

    Feel old yet ?

    USB C is awesome, but I doubt it will replace the C13/C14 power cables completely because even though it can handle quite a lot of power, it doesn't come close to those "old" cables.
  11. Yes, here in Europe I have seen stuffed cabbage, stuffed bell peppers, stuffed tomatoes, they are not that difficult to find. Stuffed grape leaves are quite different though in my opinion, both in terms of texture and taste. You can easily find recipes for stuffed grape leaves in Greek, Persian and Turkish cuisine (and probably in many others as well). Sometimes, shops also sell canned grape leaves in salt water that you can use to make that dish. The alternative would be to find a restaurant in your area that has stuffed grape leaves on their menu.
  12. greenhorn

    When you're in Court and you get tired:

    On this forum, I would have expected to see a computer case instead of a briefcase
  13. greenhorn

    [quote] y'all wanna impeach president [student…

    My brain at almost 2 am (which is the time right now where I live): Does the English language have more words that consist of "im + [name of fruit]" like the word impeach? There is impair (which sounds like im-pear). I guess a few neurons have misfired in my brain and I should get some sleep.
  14. I have had stuffed grape leaves several times with different stuffings and both hot and cold. I think I prefer them cold because the flavours turn out differently. When it comes to fig leaves, I am more skeptical (didn't try it yet). Those leaves should be quite difficult to chew and also when you break off a fig leaf, there is a milky, sticky liquid with a distinct odour coming out of the stem. I'm not sure how that tastes. Maybe they are ok if you cook them long enough.
  15. There is a new type of diet called the see food diet: Every time I see food, I eat it.
  16. greenhorn

    I recently started taking "ice baths" after doi…

    That sounds interesting. From my experience, when taking those cold baths, the body starts breathing very quickly, but one can concentrate on having slow, regular breaths and the cold becomes bearable quite quickly. After a while, there is a feeling of numbing cold, particularly in the extremities (hands and feet), which I guess is caused by the way blood circulation works in the body. Probably the body will get more and more used to the pain and/or perfect the internal heating mechanisms to better counteract the cold. When you say that you are doing workouts blindfolded, are you also refering to the cold baths? I guess doing it blindfolded or closing the eyes during the baths could be helpful.
  17. That method is interesting, but it can be abused (as can all tracking methods). From what I have read, I think it could be also be circumvented by randomizing some GPU parameters like clock and voltage in a small range, so that it is not noticeable for the user but still manages to throw off that tracking algorithm.
  18. I recently started taking "ice baths" after doing a few breathing exercises as described in the Wim Hof method. A couple of friends and I go into a cold river (water temperatures ranged from 2.5°C to 5°C so far) and we stayed between 1 and 2 minutes with only the head above the water. It is quite an unusual experience, I am surprised that the body can take it so well. The feeling you have when getting out of the cold water is really good.

    I wonder if anyone here has also heard of this or even tried it and has some thoughts on this? Obviously, this kind of activity can be dangerous for some people, so everyone who is thinking about trying it should inform themselves properly.

    1.   Show previous replies  2 more
    2. greenhorn

      greenhorn

      That sounds interesting. From my experience, when taking those cold baths, the body starts breathing very quickly, but one can concentrate on having slow, regular breaths and the cold becomes bearable quite quickly. After a while, there is a feeling of numbing cold, particularly in the extremities (hands and feet), which I guess is caused by the way blood circulation works in the body. Probably the body will get more and more used to the pain and/or perfect the internal heating mechanisms to better counteract the cold.
      When you say that you are doing workouts blindfolded, are you also refering to the cold baths? I guess doing it blindfolded or closing the eyes during the baths could be helpful.

  19. Like a Valve to vent off some Steam?
  20. That looks interesting. I have once disassembled a laptop that obviously was used by a heavy smoker before, it was quite some work to get rid of that sticky residue and the smell. But it was still worth it, it was a Lenovo thinkpad witha 2nd gen i5 and 8GB of RAM for 30 Euros a few years ago. Isopropanol worked quite well to remove that residue. A few months ago, I bought a nice used vacuum cleaner (Philips PowerPro Expert) on a marketplace for 40 Euros. I quickly noticed that it had a very strong smell of cat pee. I disassembled it, cleaned it thoroughly and bought new filters (for 20 Euros). I ended up with quite a nice vacuum cleaner for a total of 60 Euros.
  21. greenhorn

    Random quotes out of context: [quote] Eye makeu…

    I see your point, but I have also seen examples of ridiculous frames that are way too big and way too "shiny" so that they distract from the picture. Of course, as in everything, quality matters. In your example the make up was way overdone imho, but a decent make up done with some finesse can accentuate features of the eye just like a well chosen frame can go well with a picture. In the end, the thing about make up is that the person wearing it has to be happy about it, regardless of what others might think. Certain appearances might appeal to some and don't appeal to others. What is a shame is that some people who are naturally beautiful feel the need to apply large amounts of make up. I believe that in society, there is an issue with expectations forced onto others and with self-confidence.
  22. Well, I don't know any teacher with funny names, but during my electrical engineering studies I encountered a certain type of antenna called "Beverage antenna". Turns out it was named after a Lt. Cmdr. Beverage, which imho is a very nice name
  23. greenhorn

    Random quotes out of context: [quote] Eye makeu…

    Isn't doing eye make up comparable to framing a picture? Not that I find make up that necessary.
  24. greenhorn

    Just F#$& 'em Printers man:

    Let's just say I wouldn't be surprised if some people would think HP stood for "Horrible Products" or "Horrible Pricing". As far as I know, there is an old, often quoted statement that HP printer ink costs more than the same quantity of human blood.
  25. greenhorn

    Random quotes out of context: [quote] Eye makeu…

    Indeed the randomness is strong in this selection I have a quote from a university lecturer: "In theory, theory and practice are equivalent"
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