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Re: Using the cRIO to control custom lights
Hal,
The RC network is not really needed but your LED string does need some series resistance to limit the current in the LEDs. Current to the base of the transistor is limited by the 10k pullup resistor in the DSC. To fudge the calculation I start with 2 volts per LED so on a 12 volt supply, that allow for 5 LEDs in series and a series resistor. Calculating 2 volts and 20 ma for the resistor gets you 100 ohms. In reality the LEDs are less than 2 volts but as the battery output drops, the LEDs will stay on.
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Good Luck All. Learn something new, everyday!
Al
WB9UVJ
www.wildstang.org
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Storming the Tower since 1996.
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