MIRT

Been thinking about building a MIRT(Mobile Infrared Transmitter).

I think I have the code right. I just need to choose the light/LEDs. Do you think I should use a strobe light(with a visible light filter) or just use IR LEDs.

I have tested this with my Arduino Uno and 1 IR LED with my radar detector which also detects the MIRT and says "Emergency Vehicle". The single 5mm 1.2VDC 100mA 940nm LED works from about 10-15 feet away but that is inside my house so atmospheric conditions may effect that result greatly.

int led = 2;

void setup() {
  pinMode(led, OUTPUT);     
}
void loop() {
  digitalWrite(led, HIGH);
  delay(35);
  delayMicroseconds(544);
  digitalWrite(led, LOW);
  delay(35);
  delayMicroseconds(552);
}

I am intrigued to know why you chose the delay values you did 35.544 mS on then 35.552mS off

care to tell all?

With loop overheads, I suspect because that is closest to 14.00Hz. Can you tell us where you intend to test the device, so we can come along and have a laugh?

http://www.allelectronics.com/make-a-store/item/LED-912/SUPER-BRIGHT-RED-SUPERFLUX-LED/1.html

With one of these and perhaps some optics (1 or 2 lenses?) you might get a lot more than 15 ft range.

I don't think it works with visible red

In my experience red leds pour out a ton of near-IR. Look at one through a CCD camera and see if the picture shows a red dot or a white one. I get white from a brightly lit red led, the same kind of white as an IR led though not as bright.

I suppose a visible LED isn't such a bad idea; if you're going to get arrested, may as well make it obvious and get it over with as quickly as possible.

I suppose a visible LED isn't such a bad idea; if you're going to get arrested, may as well make it obvious and get it over with as quickly as possible.

In that case, I think a flashing blue would would be better.