This discussion has been locked.

You can no longer post new replies to this discussion. If you have a question you can start a new discussion

anyone else have HRM-TRI reception problems specifically on Fenix 5?

I remember reading about the Fenix 5 series being notorious for ANT+ reception problems where even Stryd had to boost their radio to deal with the problem

For awhile now I've had annoying dropout on my HRM-TRI using my Fenix 5 and having owned other HRM straps for years I knew to try contact gel and also make sure fresh battery etc.

Then I realized two things:

First, I can download the HR data afterwards because it's stored, and when I do that, the dropout disappears because it's recorded locally and then sent as a set instead of second-by-second over ANT+ (this is a feature meant for swimming but Garmin made it so you can download after any activity too)

Secondly when I use the strap with my ancient Vivoactive (v1) it works perfectly and records everything without dropout over ANT+

So it has to be the Fenix5? It's actually a Fenix 5s but I don't think that matters other than battery size and screen size.

Would be interesting if anyone can confirm this behavior.

If so, replacing the HRM-TRI won't fix the problem because it's the watch itself.

Which is crazy because the watch on my wrist is literally less than a foot away from the HRM transmitter at all times.

This also is starting to make sense to me why I get messages on the Fenix during my run that the HRM-TRI has connected (again and again).

(remember, there is no disconnect on other watches)

0 Rocket III over 3 years ago

Hi Rins,

I experience the same problems like you do. At first I had a HRM Run, but due to the readings falling away on the watch display during activities I turned it in for a HRM Tri. Not that I’m a swimmer or a cyclist, but it was because of the colour. My wife also has a HRM Run, and in happened occasionally that I took hers on a run. That didn’t work well

But having a new HRM didn’t solve the problem of the failing readings on the watch, a Fenix 5. I noticed that it is on outdoor runs that the problem is worst. On the treadmill I also experience false or no readings, but not that often. Until now I thought it was because I get more sweaty on the treadmill, and the HRM Tri fails to register heartbeats on my wind dried skin in the outdoors. I didn’t knew of the existence of contact gel, till now, reading this forum. I thought that would be the solution to my problem. But reading your story makes me doubt. I also get the readings of “external heartrate sensor connected” during runs, same as you do.

If I add my experience on the treadmill to your experience I think it is possible it has something to do with the battery that is to weak to feed both GPS system and the ANT+ for the heartratesensor. And if there is not enough power to feed both, it is just a matter of priority : the HRM gets disconnected.

I will do some experiments with GPS settings on my next runs and see how HRM reacts on this. I will be back on that one soon.

Greetings, Tom

0 Rocket III over 3 years ago in reply to Rocket III

Just did a 1 hour outdoors run with GPS switched off : didn’t help a thing. Heartrate signal fell away all the same...

Next thing I will try is switching off bluetooth connection with phone.

0 rinserepeat over 2 years ago in reply to Rocket III

I'm convinced the radio or antenna on the Fenix5 series is garbage but Garmin would never do a recall because no-one can prove it conclusively and they don't feel liable.

Even my stryd pod sometimes disconnects/reconnects several times during a run, my tempe will occasionally "ghost out" on the fenix5 and when I used another watch at the same time on my long runs, it's able to see all those sensors without dropout.

Stryd says they had to boost the signal on the stryd v2 pod just to deal with the Fenix5

Even DC Rainmaker mentions it: "Increased antenna range to deal with Garmin’s poor Fenix 5 lineup antenna reception"

What's crazy though is the HRM-TRI is literally just a foot or two at most at all times from the watch, and the Fenix5 can't even handle that.

I wonder if somehow a metal antenna strip could be embedded in a watch strap and connected seamlessly via the connecting pin to the Fenix5 metal case