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  1. hevans1944

    Extending output cable of auto battery charger/maintainer

    Schumacher has a web page of FAQs (Frequently Asked Questions) that perhaps @Ed Sowell should read. Responders here might want to check this page too. Based on what little information has been provided so far, I would suggest extending the existing battery cables with 14 AWG insulated wire. If...
  2. hevans1944

    COVID-19

    What most of the world may not appreciate is the United States is a federation of independent, sovereign, states (currently fifty in number) who are united under a federal government for the mutual benefit and protection of ALL the states. The vacuum in my current federal government is NOT...
  3. hevans1944

    Coronavirus transmission prevention device.

    @Audioguru: It really is too bad that schools (apparently) do not teach children, who then grow up to be stupid adults, the importance and practicality of situations that generate exponential growth. Compound interest was the stellar example that I learned when I knew enough math to appreciate...
  4. hevans1944

    Relays

    There are no stupid questions, but I have seen a LOT of stupid answers in my life. So, ask away! Also, see @bertus second and third tag lines at the bottom of each of his posts with regard to his opinion (and mine) regarding so-called stupid questions.
  5. hevans1944

    Coronavirus transmission prevention device.

    Short-wave UV is ionizing radiation, like x-rays and gamma rays, but less energy per photon. When a molecule is ionized by radiation it absorbs a photon and loses one or more electrons. This makes it really difficult to put the molecule back together again, especially protein molecules which...
  6. hevans1944

    Relays

    Yes. Generally. A 5V relay board will have relays whose coils operate from 5V DC and a 12V relay board will have relays whose coils operate from 12 V DC. The switching contacts of the relay(s) on either board are isolated from other circuitry on the board, including the switching contacts on...
  7. hevans1944

    Relays

    That wasn't what I was thinking. I was thinking more along the lines of the picture below with the DPDT switch replaced with a DPDT relay (a relay with two Form-C contacts): But your link to the H-bridge arrangement works well with two Form-C relays, and it doesn't require another relay to turn...
  8. hevans1944

    Coronavirus transmission prevention device.

    Short wave-length ultra-violet has been used since about the early 20th century as a disinfectant, with side benefits of ozone generation which some people believe is healthful in small doses. Ozone is what you smell after a heavy thunderstorm goes by overhead. It is caused by cloud-to-cloud...
  9. hevans1944

    Searching for Solder

    They DO make unleaded bullets! For use in indoor shooting ranges so everyone can breathe cleaner air. Also shotgun shells must use steel shot for migratory waterfowl hunting. Seems not enough birds were dying from lead poisoning in the air and instead were dying from ingesting lead pellets that...
  10. hevans1944

    Relays

    "Relays" is always a good topic for beginners. They do come in handy for controlling all sorts of things. There are basically two types of relays available to the hobbyist today: electro-mechanical and solid-state. These both come in a variety of operating voltages used to actuate or energize...
  11. hevans1944

    Searching for Solder

    Oh! :eek: At one time, perhaps 1968 or 1969, shortly after I had purchased my pistol, I had a co-worker who also happened to own a 1911-pattern pistol (a Taurus, made in Brazil IIRC). He liked to shoot a lot, so he saved his brass from the shooting range and reloaded it at home. IIRC, he also...
  12. hevans1944

    Relays

    You don't, only a moderator or the owner of this forum (either one) can do that. If you were to ask a moderator to do combine two or more threads, you would need a NEW subject or title that is representative of the project the combined threads discuss. For example, let us just suppose that the...
  13. hevans1944

    Relays

    Okay, fine with me. Below are my thoughts on why I thought this thread is a fork of the previous thread. I thought this thread and the previous thread was about a project. My bad. @Bluejets comment in post #6 about deja vu led me to find the previous post from which I thought this thread was...
  14. hevans1944

    Searching for Solder

    Only makes sense if you believe your body can absorb lead by breathing soldering fumes (which arise from the flux, NOT the molten tin/lead alloy). The vapor pressure of lead is too low at soldering temperatures to pose a significant hazard to human beings. Lead, however, may be leached into...
  15. hevans1944

    Relays

    You did. This thread is a fork of a previous thread started by @Goldhelmeth.
  16. hevans1944

    Powering a linear actuator with a battery

    Please do not "fork" your thread by posting the same subject twice (or more) using different titles. Moderators, if they catch this, will combine the threads, but why waste their time when you can do it yourself?
  17. hevans1944

    Relays

    I will repeat what I said earlier: learn about circuits. You can share the 12 V DC power provided to the Bluetooth relay module with the power supplied to its switched relay contacts to operate your actuator. The Bluetooth module is one circuit. The relay(s) and actuator(s) are another...
  18. hevans1944

    Relays

    You have to create a circuit, consisting of the 12 volt battery, contacts on one of the four relays, and the actuator. If you are going to use all four relays (for whatever purpose), you need a circuit for each relay. A circuit is a closed conductive path from one terminal of the battery, then...
  19. hevans1944

    Searching for Solder

    That DOES make Australia a MUCH safer place to live, plus being an ex-penal colony of the defunct British Empire, it's probably a GOOD THING youse guys are unarmed. Here in the States it's much different. We're a mostly uncivilized conglomerate of people from all over the world, Europe, China...
  20. hevans1944

    Searching for Solder

    The ONLY reason to use lead-free solder instead of 60/40 (tin/lead) or eutectic 63/37 alloy is to satisfy lead-free environmental protection laws and import/export restrictions involving countries that comply with those laws. The home hobbyist doesn't use enough solder during their lifetime to...
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