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  1. Um...Me123

    Microwave LCD is very dim.

    Thanks for your reply.  Starting to think no one would.  Rubber contacts? hmmm  This is the picture of the back of the area where the lcd and buttons are.  The green board seems to be just circuitry and the tanish one is the buttons along with some components (small transformer and some...
  2. Um...Me123

    LED driving

    When I meant efficient I kind of meant the oposite but thats fine you answered my question anyway. So if the LED can damage skin that's why they arent used in effect lighting then and neon and incandecent are because they are lower frequencies.  What are uv LEDs used for then?  So you can make...
  3. Um...Me123

    LED driving

    I was looking on ebay for IR and UV LEDs.
  4. Um...Me123

    LED driving

    If you have a video camera that has "Night Shot" or similar, will Infared LEDs work like invisible flashlights for the camera?  Can you just use a 555 to drive them 50% or do you use somthing else?  I don't know anything about oscillators (sp?) and just a little about 555s. Thanks
  5. Um...Me123

    LED driving

    Say you drive a LED only 50% of the time do you just multiply the amperage by 2 (when you want to)?  Is it that simple?  Then you can apply this idea to other concepts when driving LEDs.
  6. Um...Me123

    Microwave LCD is very dim.

    Our microwave has a green LCD and it is very very dim.  Sometimes you can make out the the numbers if you squint at it really hard.  It started toing this a long time ago so I dont remember how long after we got it (few months maybe?)  Very rarely I have seen it work normally but that has only...
  7. Um...Me123

    Laser question

    Is a laser diode work similar to a LED?  It will just send out a straight laser beam right?  Is there any way to make a laser beam show up in the air (a physical line--not just a dot on a surface) without using fog or some spray (like CSI)? Ii am asking this because I noticed laser diodes on...
  8. Um...Me123

    LM317 Variable power supply

    Never even when you were really young (or whenever you started working with electronics)! :P Anyway, through a tangle of wires I hooked up what I believe to be a test using a 220 resistor instead of a pot and got .59V not center tapped.  The calculator said I should get 2.5 (on a 28V supply I...
  9. Um...Me123

    LM317 Variable power supply

    Heres how I think I had the LM317 connected  so maybe you can help me figure out if it ruined.  I had the Vin wire conected to the ADJ--the ADJ wire connected to the Vout--and the Vout wire connected to the Vin.  Do you know if this would ruin it and is there a way to test it?  I did try it not...
  10. Um...Me123

    LM317 Variable power supply

    I think I have things hooked up the right way now but as usual there are still problems. First hooked it up and got a steady 19V out, the pot doing nothing. Measured the ohms on the pot and it seemed pretty messed up.  I think I was getting somewhere between 1k and 5k most of the time. I...
  11. Um...Me123

    LM317 Variable power supply

    Any ways to de-solder when you dont have a pump or wick?
  12. Um...Me123

    LM317 Variable power supply

    O S**T!! THE LEFT TAB IS THE ADJ.?? COULD HAVE SWORN I SAW THAT THE LEFT WAS IN, CENTER WAS ADJ, AND RIGHT WAS OUT!!!! If the left really is the adj what have I ruined?
  13. Um...Me123

    LM317 Variable power supply

    No protection diodes.
  14. Um...Me123

    LM317 Variable power supply

    Weird things... Yes I believe it did go below 1V, I think it went to .7V. I tried it again not center tapped.  I got an output of 39V (how' s that happening?) no matter where the pot was.  Get this,  when the pot was at the one extreme it would make a slight buzzing noise and make a bad smell. ...
  15. Um...Me123

    LM317 Variable power supply

    I have built this supply and was testing it before finishing up some wiring then assembling it in the box. I was using a 25V @ 2A transformer and had it center tapped for the test.  As I adjusted the pot it would jump directly from around 10V down to 1V or lower.  What's causing this? Thanks
  16. Um...Me123

    Long distance car sensor.

    This is a complicated issue and I'm a beginner at electronics.  I can't explain everything now but I need a way to "see" a car where it can't be visually seen.  There is a limitted area I can put sensors, recievers etc. but I will try to make a diagram eventually.  For right now i just need to...
  17. Um...Me123

    BENCH POWER SUPPLY

    This is what my idea has been.
  18. Um...Me123

    BENCH POWER SUPPLY

    That switch is controling a seperate mains circuit from the transformer one (in the same box though) I was thinking...I am getting a 12' power cord that is the basic cord you would see on normal stuff (like the one on your soldering iron-2 conductor that is) to power this whole box.
  19. Um...Me123

    BENCH POWER SUPPLY

    Is it safe to use a DPDT LED lighted toggle to control mains and use the other half to control the LED so it turns on when the mains is on.
  20. Um...Me123

    BENCH POWER SUPPLY

    OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO :o ;D I get it now.  The DPST (or at least the type I was talking about) is designed for turning mains (thats what you call the 120V AC from the wall?) on and off and thats why that neon is bridged between! Ok so about those relays...you say to put a...
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