Quote:
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Originally Posted by Damian Manda
Ehat camera did you use for this picture? My camera can hardly see anything when pointed at the beacon.
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Camera used: Olympus 3040, digital, 3 megapixel, flash off, macro focus on
This photo was taken with an IR LED powered from a
5 VDC voltage source drawing .11A (33 ohm kit current limit resistor)
i.e. 100% ON duty cycle....
to make it easy for the digital camera to see.
See my other IR Beacon photos in the gallery
showing the much dimmer (but visible) LED illumination when pulsed/burst
<1 mS burst of 40 KHz pulses, & low duty 100Hz rep>
emitter 0:
pulsed at 40 kHz (50-50 duty square wave)
burst for 40 cycles = 1mS (total ON time = 500uS)
and 100 Hz repetition rate (total Off time = 9500uS)
500*100/(9500+500) = 5% ON duty time
use emitter 1 (to improve cameras ability to see IR a bit)
80 cycles = 2mS (total ON time = (.5*2mS) =1000uS)
and 100 Hz repetition rate (total Off time = 9000uS)
1000*100/(9000+10000) = 10% ON duty time