Timex Ironman Heart Rate Monitor Watches Compared http://www.sportswatchinformant.com/timex-ironm... All Timex Ironman heart rate monitors include a digital FM signal that reduces crosstalk and interference with other HRM devices, ECG (EKG) precision, shown by independent testing to be accurate to 3 beats per minute and a user changeable sensor battery. This chart provides a feature-by-feature comparison of watches in the Ironman range that suppor
