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Everything posted by Externet

  1. Thank you sir, +1 What is "improve" ? Makes it less or more diverging?
  2. Thank you. The failed embedded image was just a generic one like : What if possible could be the way to obtain one Km long 10cm diametre fat beam as close as possible from start to end ? These are outdoors ---> https://www.youtube.com/watch?v=RmcQNiNHemc - ---> https://www.youtube.com/watch?v=uYKERtq_L5M
  3. Seems that if a laser beam is bigger than about 2 mm diametre it is not a laser any more ? Or is it still a laser even if the beam is 1 metre diametre ? How is that accomplished ? Diverging lens and collimator after ? The danger of vision impairment persists or is it greatly reduced as the light 'density' is a much smaller figure ? Which wavelength shows the beam brighter at night ? To achieve 1Km range on a 10cm fat beam at night, what power would be needed by educated guess ?
  4. Hi. Can you instead of comparing the cost$ for time lapses, tell/compare KWh of consumption for the lapses ? My local energy is supplied typically by gas and/or electric. Eliminated the gas years ago and am using electric heat only, because the gas company wanted to charge a monthly minimum even for zero consumption to 'maintain' the account during ~8 not-cold months of the year. So kicked them out in 2016, not willing to 'maintain' their pockets besides peace of mind with no gas in the dwelling. Make sure you are not in that kind of trap, or utilities 'policy' changes. (Am heating only the rooms in use, 3 bedrooms have heating shut off and closed doors) As other means of not wasting heat and money.
  5. I would explore routing/passing the water mains into a radiator inlet inside your apartment and returning its outlet to the building supply. You would be extracting only its coolness. Enclosing the radiator would limit how much cold you get. Adding a fan trough the radiator would increase the cooling. Main water into building >---------------------------------------A cut B---------------------------------->building supply Insert a radiator inside your apartment between A and B; and wear a jacket. A window air conditioner is an alternative that can cool the whole apartment if doors are left open; and is not expensive. I have a 5000BTU that hangs on the window during a couple of months and goes back to storage in winter. I would not consider anything Peltier. Inserting a pass valve between A and B in parallel to the radiator would control the flow and the resultant dwelling temperature; no need to enclose the radiator.
  6. Remember dealing with the Réaumur scale in high school, the equivalent formula was dividing by 4. But was never taught about Rankine.
  7. And maaaany more oddities in USA as the ounces, feet, inches, gallons, pounds, furlongs, fathoms, knots, MMDDYY, small, medium and large; twin, queen, full, king , AM/PM, acres... They just missed to drive on the left lane 😊
  8. Welcome. What is the temperature of the water mains supply in summer; and the temperature of any ground source water well available to tap in the vicinity ? Are you allowed to install a 'window' air conditioner ? Are you allowed to glue styrofoam on your room interior surfaces ? This has to be near 100 euros
  9. Thanks. Now am done scratching my head... If Betelgeuse explodes tomorrow, its 'little bang' will spit matter expanding in all directions away from wherever in the Orion constellation it is today. That will be its point from where it expands. How does the "All points" refer to it if you are observing it from planet earth or observing it from Antares at Scorpius ?
  10. Hi. Where in the universe is the point all galaxies, planets, celestial bodies are moving away from in their expansive motion ? Is that point consistently the one and only same for all constellations ? Is there any curving/bent trajectory ? Am sorry for the poor wording.
  11. Hi. These are double pane windows from 1990 in excellent condition for their age. Their poor design conducts the frame cold from the outside to inside. Adding a 'storm' window would be on the exterior as far as i know; not preventing much of the outside cold to reach the frame. If investing on them would give a cure am not against the cost. What am against is investing for no improvement. I have laid a towel strip on the sill and collects the running moisture and improves the problem with the towel treated with bleach, ammonia, vinegar... The nature of the towel wicks and evaporates the moisture decently but not perfectly. Just wondering of your 'magic' had better bullets than mine... Thinking on gluing wood or vinyl strips to the interior surfaces... By the way... which single household chemical in the towel would deterr mold better by proximity ? Ammonia, bleach, vinegar, other ?
  12. Thanks gentlemen. I did try single sided adhesive 3mm foam on the inside window frame as insulation coat, not that brand; did not stay stuck to the aluminium 😤 Keeping the area dry is much easier typed than done. A dozen windows of ~2mx1m in half a dozen rooms... A brand of bleach left crystals after spraying dried and prevented the mold for a lot longer, but not the condensation 😞
  13. Greetings. Aluminium windows of goofy design transmit/conduct the sub-freezing exterior to the frame interior causing condensation and mold. Applying chlorine bleach kills the mold instantly; but would like opinions on a powder/solid 'chalk'/drying film spray applicable to the frame to prevent long term the mold from forming.
  14. Thanks, gentlemen. Revisiting the basics of the thread; - The photovoltaic generation (~3KW) to be used solely for dwelling heating day and night, no cooking, inverters, lights, grid feed... If appears makes no money sense; OK, that is not a purpose of the discussion. - The preference to not use batteries is because of added cost, maintenance, fumes, weight, and they are not storing heat. And if lately is sunny and batteries got full charge, today is not cold enough, why 'waste' the irradiation as batteries cannot store more beyond full charge state ? An extra barrel of water 'inline' or raising rocks a few degrees more is still in reach instead. - The material to store heat from electric heating elements in adequate barrels can be stones, concrete chunks, oils, iron scraps, water. Which would store the most heat per volume regardless of convenience or cost ? To deliver heated air, heated fluid to proper ducting. Fancy state-changing chemical salts are beyond consideration to keep simplicity. 10m underground depth geothermal storage is not preferred when an ample basement is available.
  15. Doesn't the inclusion of batteries introduce more losses in charging, discharging, maintenance, shorter life and wallet losses ? Seems that if what is wanted is heat; then make heat directly from photovoltaics. Heat leaks/losses of a hot water reservoir are still providing heat inside the dwelling as intended. ======================================================================================== Ken : Important charts if this is what you are after : Deeper than 10m, soil temperature is stable; and temperatures likely to find at certain dates by depth in order to harvest its heat (or cold)
  16. Thank you. Electric powered hot water reservoir circulating into a radiator inserted in a dwelling HVAC ducting for heating in winter. No other use. Over half the power generated during sunlight hours to be used for night time circulation. [3Kw of zero cost panels array on hand ]
  17. OK. Are you after that exact piece of equipment or something similar that can perform the transfer of fluid by electric driven piston ? ----> https://www.terapump.net/product-p/trpmw100.htm ---->
  18. Welcome. What is the action it performs ? Electrical input to linear servo output ? Anything hydraulic in it ? Purely mechanic ? Size ? ¿? Something similar to ----> https://www.amazon.com/Detroit-Axle-Complete-Electric-Steering/dp/B01CKKBDSU ----> https://www.summitracing.com/search/part-type/rack-and-pinion-assist-electric-steering-kits
  19. Welcome. That adhesion method and strength is what makes brakes and friction bands reliable. If a wimpier adhesive method was used, failures would be too frequent. So use an agressive method to remove such. I like grinding wheels, and less aggressive are sanding disks. Sandblasting should work too. Have you compared the amount of time and work of removal/reline against purchasing a new replacement part ?
  20. Hi studiot. That link took me to several others and saw/learned about impressive whiskers formation; for sure unexpected when equipment was built decades ago. Thank you !
  21. Greetings. A LED emitter can have a long life. Even longer if underdriven from specifications. Asking for an educated guess... A LED designed to operate on 1 Watt of power, if energized to 1/10W; would it last 10 years ? 100 years ? Same question if it is a laser diode.
  22. Thanks. Seems then the sudden heating of air from the spark expands the air and the 'crack' sound wave produces the shaking of the spheres. Acoustic motor 🙄 like windows in thunder.
  23. Hi. Another video 😉 but short and no need to see it all; just time stamp 0:30 shows the spheres shaking. How is the spark producing forces ? I could imagine if they where suspended, the motion would show greater. ----> https://www.youtube.com/watch?v=s8704VbBKbw
  24. Thank you, swansont. Agree with the direct path to ground. The explanation at the beginning with the charged cloud? layering sketched at a certain height is not as convincing as the demonstration at time stamp 4:15 ----> https://www.youtube.com/watch?v=zhu5pIrPw7U (it is worth seeing, not a waste of time) The NASA launch pad may show a concept malfunction, if strikes prefer the rocket : When surrounded by lightning rod poles. Something is not making sense, besides the unpredictability of the phenomena.
  25. Hi, good day to all. Two identical houses (materials, height, shape) are next to each other but only one has a lightning rod installed. Other houses in the immediate neighborhood have no lightning rods. A block north, and a block south, and a block east and at a block west there is houses with lightning rods installed. An electric storm is more probable to strike the lightning rod on the house that has one or the roof on the identical next to it ? In other words, a lightning rod attracts and conducts electrical strikes to ground or forms a zone that prevents the lightning from striking ?
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