Search results

Search Forums New Posts
  1. hevans1944

    Suitable material to filter UV out of halogen lamp

    I think most plastics will stop UV radiation, but the downside is the UV will eventually destroy the plastic by breaking the polymer cross-link bonds (photo-dissociation). You would need to find a particular polymer, such as polycarbonate (Lexan), and then find the spectral transmission...
  2. hevans1944

    Suitable material to filter UV out of halogen lamp

    Try this one... It has a sharp cut-off for wavelengths shorter than 400 nm.
  3. hevans1944

    Suitable material to filter UV out of halogen lamp

    Google is your friend here. Salt would probably work, but why bother? Doped quartz is the method of choice and is readily available.
  4. hevans1944

    Where to buy these pins?

    I used to wonder how they collected "product" used in the breeding of prize animals, such as stud bulls and stallions. Now I know, but that search led down some "interesting" paths. Animal husbandry is a fascinating subject.:D
  5. hevans1944

    timed relay adjustmemt

    There are plenty of people here at Electronics Point that can help you if you want to build it yourself. If your solenoid operates from 12 VDC it would be simple to actuate it with a power MOSFET. OTOH, if you needed a relay to switch AC power to your solenoid, this is easily done with a TRIAC...
  6. hevans1944

    Suggestions for replacement of an electromagnetic changeover relay

    You could also rectify and filter the line voltage to operate a different relay with a DC coil. These don't make any noise when actuated. @Tha fios agaibh gave you good advice: don't try to switch between the mains and your inverter with a solid-state switch. Not only is it not fail-safe, it...
  7. hevans1944

    Where to buy these pins?

    Welcome to Electronics Point! It appears you can purchase what you need at the link you provided. A bit pricey, in my opinion. Try looking in an on-line U.S. electronic distributor's catalog. Might also try a Google search. Hint: TENS machines and similar devices are popular "toys" used for...
  8. hevans1944

    timed relay adjustmemt

    So... you push a button and nothing happens. Release the button and a variable amount of time later, adjustable from 20 milliseconds to 70 milliseconds, the solenoid is energized and remains energized. Did I get that right? How do you de-energize the solenoid? What is the HMI (human-machine...
  9. hevans1944

    12V power supply and 12V battery charger

    And so were mine! But at least I didn't have to change my underwear.:D Not so sure about my brother.
  10. hevans1944

    timed relay adjustmemt

    Well, please let us know what you find that may be useful. How do you intend to turn the solid-state relay "ON"? That could have an impact on how you delay the turn off. Also, does the solenoid really draw 10 amperes when energized? There are some solid-state relays available that are about the...
  11. hevans1944

    Forward Current, Forward Voltage, Reverse Voltage...

    Forward Current, Forward Voltage, and Reverse Voltage are typically specified for diodes, and in bi-polar junction transistors or BJTs for the base-emitter and base-collector junctions, which are also diodes. The forward current is always accompanied by a forward voltage and represents the...
  12. hevans1944

    New here. Just learning.

    Welcome to Electronics Point! Feel free to ask about anything electronical. There is probably someone here who can help you, or at least point you in a direction to look for more information. It's all free, too, because we enjoy helping others, especially beginners, explore the fascinating...
  13. hevans1944

    timed relay adjustmemt

    Is it this one? If so, please note that, depending on how the two switches are set, the release time can extend to as long as 900 seconds. This is probably controlled by selecting the output of an internal counter for the longer intervals, with an adjustment to set the frequency applied to the...
  14. hevans1944

    Need help with Bose Wave Radio AWR1-1W Series 2

    You might want to consider a professional repair service such as this one. Or Google for others.
  15. hevans1944

    timed relay adjustmemt

    Welcome to Electronics Point! Please provide more details about what you are trying to do. What is the part number or model number of the Hella relay? Is it delay on release, or delay on actuation? Electromagnetic relays require a finite minimum time for the contacts to transfer, so three...
  16. hevans1944

    12V power supply and 12V battery charger

    A 12V power supply is typically well-filtered after rectification of the line voltage, providing a steady DC output that may be voltage or current regulated as well. A 12V lead acid battery charger is typically not filtered, or minimally filtered, after rectification of the line voltage because...
  17. hevans1944

    Solar Power Distribution

    Welcome to Electronics Point! You should start by telling us what your project is. The solar panel and battery pack you linked to are for charging cell phones and tablets. 5 VDC low-power stuff. The motor you linked to is typically used to drive the propeller of a model airplane, which is a...
  18. hevans1944

    hospital yet again

    Please get well soon, Dave! Hop
  19. hevans1944

    MCP2221 USB to UART/I2C. Confused.

    Go here and scroll waaay down to find the I2C commands, which appear to be 64-byte messages sent via USB.
  20. hevans1944

    What can cause logic glitches

    Biggest source of glitches is inadequately by-passed power supply rails. Each time a high-speed logic device changes its output state, a current pulse occurs at the power supply input to the device. This pulse can then propagate as a "glitch" over the power supply rails to other devices. The...
Top