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  1. CDRIVE

    220v LED DIMMER??

    As Kris has explained repeatedly you can't avoid power dissipation losses when using a linear current limiter, voltage regulator etc. You mentioned a variac earlier. Though large, it would be an efficient method with very low power losses. A multitap transformer would also be efficient. Chris
  2. CDRIVE

    Common-Base amplifier explanation?

    I still have old text books that teach electron current flow from negative to positive. As I said earlier either convention will work as long as they're not mixed. After all I'm never going to see an electron. ;) Chris
  3. CDRIVE

    Common-Base amplifier explanation?

    Electron flow is always from negative to positive regardless of NPN or PNP, Common Base, Common Emmitter or Common Collector. Note: Electricians in the U.S. are taught that current flows from positive to negative but this is in opposition of higher level electronics teaching. It really...
  4. CDRIVE

    Common-Base amplifier explanation?

    Harald, this is exactly the identical information we have in my link. ;) Chris
  5. CDRIVE

    Common-Base amplifier explanation?

    Welcome to EP. We have a tutorial section that covers the BJT Common Base Amplifier. See if this helps. https://www.electronicspoint.com/common-base-amplifier-t222884.html Chris
  6. CDRIVE

    Oil level monitoring project using capacitance level sensor

    Welcome to EP Russ, I'm assuming this is a large tank. So, I'm also assuming that this voltage drops very slowly. How long does the alarm delay have to be? A 555 timer works well for short delays measured in seconds. Longer delays and freedom of how to sense this is best performed by a...
  7. CDRIVE

    New Career?

    I've seen this video before and yes it's scary. What I don't get about the video is what the maintenance was. He equalizes the charge between the line and the helo, hops on the line and shimmies along it. Then the Helo returns. He equalizes again and re-boards the Helo. Other than that we have...
  8. CDRIVE

    alternating LED flasher using 12Vdc supply and 555 timer

    We have one here. https://www.electronicspoint.com/3v-2-led-flash-circuit-t247808.html#post1465558 Chris
  9. CDRIVE

    New Career?

    I don't have fear of heights. I have a fear of uncontrolled gravity feed to earth. :D Chris
  10. CDRIVE

    Denser than Osmium

    I somehow missed that topic and I'm glad I did. As for you getting p!ssed off, .. it surprises me. You have such a gentle and mellow face. I guess even you have a breaking point. :p Chris
  11. CDRIVE

    New Career?

    Ya have to have cast iron huevos to do that work. During my 16 years as a Bio-Med contractor at a local hospital I also maintained their communications equipment. When the tower light burned out the management inquired what department had the responsibility for its maintenance. The engineering...
  12. CDRIVE

    Wheel movement sensor / alarm

    Photos can be attached to your posts here. As for messy.... I don't expect the operation to look like an office cubical. I like messy! It'll make me feel at home!!! Though none of my neighbors have never complained I suspect they grumble when I use my saw dust as fertilizer. :D Chris
  13. CDRIVE

    Wheel movement sensor / alarm

    I don't like doing this because it's bad forum decorum to post three times consecutively but I promised you I'd elaborate further after some sleep. Before we start talking about details I would very much like to see photos of the control panels of each of your motors. If you can extract the...
  14. CDRIVE

    Time Delay Relay for Digital Frame

    The first thing you need to do is determine if your Frame's 'Next' button switches to the low or the high power rails when pressed. It's more than likely (>90%) that your button switches to the low (negative) rail but you have to test this with a multimeter. Testing with no power to the...
  15. CDRIVE

    Wheel movement sensor / alarm

    You posted this right after my last post. It's 0130hrs here and my eyes are getting very heavy. I'll go into detail tomorrow. ;) Chris
  16. CDRIVE

    Wheel movement sensor / alarm

    Yes, it's more than feasible to kill all the machines if you like. Is this a pulp mill? Chris
  17. CDRIVE

    Time Delay Relay for Digital Frame

    Are you familiar with the 555 timer chip? It will easily facilitate this. Chris
  18. CDRIVE

    Wheel movement sensor / alarm

    After re-reading this you may want to consider having the circuit kill the 3PH motor with a 3 pole contactor. After all, by the time you respond to the alarm the belt may be toast. If the motor already uses a latching magnetic contactor we can probably tie into the control side of it. Chris
  19. CDRIVE

    Wheel movement sensor / alarm

    Yes, what EB described is called Quiescent or Static Biasing. It will greatly increase sensitivity. Great care must be used when setting forward bias near threshold voltage of the BE junction though. If temperature rises Q1's beta will increase and cause the LED to be on constantly. Adding a...
  20. CDRIVE

    220v LED DIMMER??

    Kris, if in the future, discrete circuit design achieves the collectivity of the art world's minimalist and impressionist periods this will have to fit in your 'Mega-Maximumist' period. :p GottaI love it for it's "WTF!" value! :D Chris
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