[Tom Goldman]

LED's opperate on DC voltage. ...if they were visably flashing on the ultra slo mo. ,it's possibly from the rectifier bridge being used in the power supply. .....Another possibility ,altho I doubt NHRA would be this sophisthicated is they are using pulse width modulation to dim the lamps......That would eliminate the need for those hi tech flood lamps the use on the tree at night !!.................Yes, I was an electronics geek in a past life. .....Tom