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fishycomics Feb 10, 2006 3:18 PM

keep some tabs and instructions on it go to freewebs and sign up and do an instructional video and pic ther.

MPVRr Feb 10, 2006 3:26 PM

Will do!

MPVRr Feb 11, 2006 3:19 PM

Well...the IR thing is a bust. 4 IR LEDs do nothing to illuminate a dark area. I'll be experimenting with white LEDs next.

fishycomics Feb 11, 2006 4:11 PM

got a whole bunch here I tried four I tried 8 in a flash light I just stuck to a reflector light lol

here is a 40 watt reflector I hada 60 watt incadecent up here some where lol

see it is dark atfirst but when I moved in and light is just behind got lighter I bet if I move in front of the camera it will light up

juandelacruz Feb 13, 2006 7:26 AM

Color cameras are deliberately insensitive to IR. manufactures put IR filter in the lens because IR will interfere with color. true night vision cameras are the black & white ones. Other cameras equipped with night mode (like my sharp video CAM) have a mechanical lever todisengage the IR filter and the IR illuminator ( high power IR leds) will be turned on. Its quite neat because you will be able to see in complete darkness up to th power of the IR illuminator.

If you want to make your DV6800 IR sensitive, you have to remove the filter but will make the color system useless.

About LEDS:

Blue, psedo white and white LED's are different from ordinary Yell, Red or Green LED. The rating of the blue and white is approximately 4.0 volts at 30 mA while the old LED's (red, green, yellow ) is about 1.7 to 2.2 volts at 20 mA.

You can conect in series and parallel to obtain the seried voltage but if the supply is higher that the LED voltage, you better use a resistor, examples:

3- white LED if connected in series (watch out for the polarity) can be connected to 12 volts max.

If connected in parallel can beconnected to 4.0 volts max. If you want to connect to 6 volts then you need resistor, computation as follows :

assume 30 mA each, 3 diodes will draw 3x30 = 90 mA

Voltage to be dropped by resistor = 6volts - 4 volts = 2 volts

Required resistance (by ohm's law): 2volts divide by0.09 amps or 90mA= 22 ohms

Youre in luck because 22 is a standard value, other standard values are 18 and 27 ohms.

For power rating , again by ohm's law: 90mA Squared X 22 ohms = 0.178 watt, the closest value is 1/4 watt.

Summary, for 3 white LEDs to be connected to 6 Volts source, you have to connect 22 ohm, 1/4 watt resistor inseries.

Of course you can always connect the LED directly to the 6 volts source, depending on the power of the battery I do not know how long (sec or min) the LED will lasts.

I hope I did not bore the readers ;)

MPVRr Feb 13, 2006 11:32 AM

Whew! This is good stuff. Thanks!

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