Originally Posted by
Rich Gibson
...The mini ANT USB stick consists of a cable adapter (micro USB to USB (F)) and the device for $53.00. So...when you have that you also need an ANT+ HRM..right? I bought an Axiom HRM for $39.95 at Performance Bikes a few weeks ago. It works fine but I wondered if it may be ANT+ compliant? (I think not). The reason is I have a Life Fitness Elliptic which has a heart monitor but you have to hold both handles and contact the silver metal plates on each bar for it to work. It's kludgy, but it works. Well, yesterday I put the Axiom HRM on and lo and behold the heart rate started showing on the Elliptic console even though I wasn't holding the handles.
It had to be the HRM because it mirrored the values showing on the HRM wrist band. It also changed in sync with the wrist band.
Does anyone know what the heck is going on here? What type signal is the Axiom outputting?..
First I'm no expert is such matters but my thoughts on the matter; The handles of your elliptical are acting like antenna and are picking up the signal from the HRM transmitter you are wearing. At least this is my guess. Since the signal is designed to be read by an outside source ( wrist or bike monitor ) I think it just a coincidence that the HRM on the elliptical is able to interpret the signal.
Often times you hear about people who have wireless devices who suddenly have their devices stop working. Usually this is because another electromagnetic field ( or signal ) has come into close proximity to the device. When this happens the outside source will either be so strong as to completely drown out the other signal or the two signals will mix in the effect that has been electrically defined as "Heterodyning". With heterodyning, two signals mix and end up producing a signal that is equal to both added together. Since the device is not able to process such a signal it would appear not to work.
I remember one time when I was a kid I got an airplane radio transmission over my "Combat" walkie-talkies. Only lasted a couple seconds but I thought it was cool. If the signal is close enough and strong enough things happen. In this day and age with digital electronics this type of stuff doesn't happen as much.