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  1. hevans1944

    Simplest Way 13 KV To Charge A 9 KV

    It could be beneficial to obtain a Rat Zapper and "reverse engineer" it to allow you to construct three more. I would be particularly interested in how the voltage is applied to electrocute the rat. Perhaps a gridded conductive floor? Alternating conductive metal strips? Or perhaps the bait...
  2. hevans1944

    Expected wavelength output of ceramic coated heat lamp?

    Depends on the surface temperature and emissivity. If it doesn't become incandescent (like the coils on the countertop range) it probably behaves like a blackbody with most of the radiation in the 1 to 10 μm (1000 nm to 10,000 nm) range. Refer to a blackbody radiation curve:
  3. hevans1944

    Running incandescent or halogen bulb with 2/3 or lower voltage possible?

    Look again at the chart that @BobK posted: it shows radiant energy in kJ per nm. Visible light energy is the area under the curves from about 400 nm to 700 nm. Infrared is the area under the curves from 700 nm to more than 2000 nm. If you measure the two areas, the infrared energy is a LOT more...
  4. hevans1944

    Simplest Way 13 KV To Charge A 9 KV

    It is far from humane to allow a deer population to grow to such numbers that the deer seek food from men. Here is Ohio, such misguided attempts in the past have resulted in deer devastating crops, even entering and destroying green houses, because of their large numbers. Controlled hunting is a...
  5. hevans1944

    volumetric display project

    Sorry 'bout that. I guess I did. If it pleases you to get involved with this "technology" then my all means do so. At the very least you will learn a lot and have a wonderful conversation piece to display.
  6. hevans1944

    how do I make pulse oximeter

    I have to wonder about the motivations of your teacher. A pulse oximeter is not simple to build, and a microprocessor is invaluable in converting the raw light transmission data to blood-oxygen percentage. There are also (patented) algorithms, easily implemented with a microprocessor, that are...
  7. hevans1944

    Running incandescent or halogen bulb with 2/3 or lower voltage possible?

    Thin aluminum foil will probably absorb much of the infrared radiation and will become warm. A small fraction will be reflected. Astronomical telescope mirrors are often coated with a thin film of aluminum (because it is inexpensive), but astronomers don't generally worry about the infrared...
  8. hevans1944

    mosfet diode

    You are probably thinking of MOSFETs used as synchronous switches for rectification. The advantage is the very low voltage drop across the device when is is on, and the high impedance when it is off, meaning the MOSFET dissipates very little power compared to an ordinary diode rectifier. The...
  9. hevans1944

    volumetric display project

    I hate dithered images. Reminds me of the dot-matrix printer days. The direction of technology is toward realistic immersive image experiences, fairly easy to obtain with high-resolution head-mounted displays and multiple gigahertz graphics pipeline processors. You will probably have noticed by...
  10. hevans1944

    CircuitStudio by Altium

    Price is several thousand dollars for the professional version of either software, but Eagle is about a thousand bucks cheaper. That is still too rich for my blood, unless I can find a "customer" I can load the cost onto. I did that once with a purchase of PADS PCB layout and schematic-capture...
  11. hevans1944

    how do I make pulse oximeter

    All good advice by @davenn and @(*steve*) . Since this IS homework... DO your homework: search the Internet and get back to us with what you found that DOESN'T require a microprocessor.
  12. hevans1944

    Beginner question: Can I convert speed fan switch to three?

    Probably not. Multi-speed fans switch in different motor windings to control the speed. You should purchase another fan that runs at the speed you want.
  13. hevans1944

    Would it be difficult to add a standard home thermostat to an electric portable house heater?

    Remove the space and the word "this" from the address bar after clicking on the link, then hit the "Enter" key to reload the page with the correct address. Or, click here.
  14. hevans1944

    8085 instruction & 8051 function "RLC"

    Welcome to Electronics Point! The 8085 RLC is NOT the same as the 8051 RLC. On the 8085, RLC copies bit 7 into the carry bit, as well as into bit 0, all other bits in the accumulator moving left one position. The original value of the carry bit is lost. Think of this as a left rotation of the...
  15. hevans1944

    Running incandescent or halogen bulb with 2/3 or lower voltage possible?

    It just occurred to me that your 12V halogen lamps will probably work just fine as infrared heaters if you lower the voltage a LOT, which will lower both the filament temperature as well as the evaporation rate (as @(*steve*) said earlier). It's worth a try anyway. Now where to get a...
  16. hevans1944

    Simplest Way 13 KV To Charge A 9 KV

    Where are you getting the 13 kV from? This sounds dangerous. What is your application? What load does the 9 kV discharge into? Will any animals be harmed?
  17. hevans1944

    HUH?????

    A wall of box fans mounted on fence posts? What would the neighbors say? OTOH, if I can throw a good-bye kiss to Dayton Power and Light, maybe K-Mart will have some on sale this year that I can buy before word of this gets around...
  18. hevans1944

    Before I start on a project - wheel re-invention protection

    The problem you will discover is building a clock with 0.01 second time resolution. Why do you want to do this? It is impossible to "read" a clock whose last digit changes every 0.01 seconds. It is almost impossible to "read" a clock whose last digit changes every 0.1 seconds. Other than that...
  19. hevans1944

    Cleaning a PCB

    Which is why I trim them shorter with a pair of scissors.:D And sometimes I wrap a few turns of tinned solid copper wire around the base of the bristles, pulling it as tight as possible, and solder that to the tinned handle.
  20. hevans1944

    Soldering Wires

    I admire your ambition. Once you get the intricacies of camera hacking down pat, I think you should consider a career modifying Rolex watches for use on Mars by future astronauts. Should be just a matter of swapping out a few gears and such to account for the longer day and (if there is a...
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