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    Re: LED conversion Astra IIIB
    From: Paul Dolkas
    Date: 2016 Aug 18, 23:11 -0700

    There are LEDs (red and other colors) that come in the standard screw-in 1.5 v bulb format. Hard to find, but they exist. When I did mine, the only red ones available were 3V, so I had to use a 3V lithium C cell to fit with the C cell battery holder in the Link 12


    Paul Dolkas


    From: NavList@fer3.com [mailto:NavList@fer3.com] On Behalf Of Bruce Cutting
    Sent: Thursday, August 18, 2016 11:44 AM
    To: paul@dolkas.net
    Subject: [NavList] Re: LED conversion Astra IIIB


    Led conversion should be easy.  The resistor will not be very effective at
    limiting the intensity - there should be a resistor to limit the current
    to the design spec of the particular LED selected though.  Calculte as
    follows R= (VB - VL)/IB  VL = LED voltage drop; VB = battery voltage, IB =
    specified LED current.
    > Dale
    > You probably want to switch to red LEDs and diminish the intensity by
    > adding another resistor in series.
    > This will help to preserve your night vision sensitivity
    > Brad
    > On Aug 18, 2016 8:30 AM, "Dale Bletso"  wrote:
    >> Celestaire said the IIIB couldn't be upgraded to LED illumination, so I
    >> coverted mine in 15 minutes.  Now no more burned out bulbs in the middle
    >> of
    >> a run.
    >> *Attached File: *
    >> View and reply to this message
    > View and reply to this message:
    > http://fer3.com/arc/m2.aspx/LED-conversion-Astra-IIIB-Morris-aug-2016-g36282

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