Dropping heart rate belt
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@Hari-Seldon thanks for the suggestion, but I don’t have a different one to test, and not about to spend on one when it works fine with other devices.
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Does that happen with the chest HRM strap, or does it also happen with the one on the watch itself?
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@Jose-Luis-Merino-Parra I’ve only noticed when using the chest strap as I almost always use that.
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@owend I have no issues with a Suunto SmartSensor belt. I do not think this is the watch. How new is the belt? Battery? The belt straps for me do not last more than 1 year at most. They wear out. The sensor is not a problem but the belts will stop sending accurate HR. You can check R-R values in Runalyzer, that would give you some indication if there are problems with the belts.
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@Brad_Olwin It’s a year old, rechargable battery, and it has been fully charged prior to one of the times I saw this issue. As I said, when I ride I dual record to ELEMNT computer which has good hr data from the same strap for the full ride, only the watch is missing data.
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@owend The Suunto watches calculate HR from R-R data, I do not know how the ELEMNT does receive HR. Check in Runalyzer, I suspect the belt is the problem. In colder weather tech shirts can cause static that can interfere with the transmission as well.
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@Brad_Olwin right so I created a couple of Runalyze accounts and imported the Suunto Run fit file into one, and the Wahoo ROAM fit file into the other. Both were taking data from the same strap during the same activity as I dual recorded.
This is the ROAM activity:

This is the Suunto Run activity:

This looks really odd. It doesn’t appear that the Suunto is missing the data at the end, as the same pattern for the final 21-27km of the ROAM graph matches the 14-20km section from the Suunto graph. It looks more like the 4-11km section from the ROAM is missing from the Suunto graph.
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@owend Check the R-R data not HR, the HR is calculated from R-R. You will be able to see how noisy the R-R data are.
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@Brad_Olwin ok this is what that graph shows for the Suunto activity. I don’t see the same graph on the Wahoo ROAM fit file:

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@owend looks good