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    Re: Heath Hezzanith question
    From: Chuck Taylor
    Date: 2007 Oct 22, 21:28 -0700
    Why not use an LED?  Radio Shack sells a 5 mm red LED for $1.99. It draws 20 ma at 1.7 volts (typical).  My sextant takes two penlight batteries (3 volts). To make this work without smoking the LED, I would need to solder in a resistor of the proper value in order to drop the voltage to 1.7 volts. But first I would have to do the math to compute the proper value for the resistor. I think I'll stick with the red marker. :-)

    Bonus question:  What size resistor would I need?

    Cheers,
    Chuck Taylor
      48 N
    122 W


    Gary LaPook writes:

    Why not use this opportunity to join the 21st century and use a red LED (light emitting diode) cheap at Radio Shack, uses almost no current and lasts forever?

    gl


    Chuck Taylor wrote:
    red nail polish on the bulb or lens.

    I use a red felt-tip marker for coloring the bulb on my boat's compass. It works well. It would likely work also on a sextant light. I picked up that trick from a compass repairman at a boat show.

    Chuck Taylor
    48 N
    122 W




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