Timex R300 broadcast hr function

I recently bought the Timex R300 smartwatch. I bought it mainly for the broadcast HR function. With the idea to connect it to my Garmin edge 520 or 530 and to ditch the dedicated heart rate strap.

But when the broadcast hr function is turned on in the watch I’m unable to connect it to any device. What’s worse it won’t even show up on any device.

Has anyone with the Timex R300 had any success with this functionality?

Maybe it only broadcasts to your connected phone (within the app, not as a bt hr sensor)…

Nope, tried that as well