Polar H10 users...have you seen issues with HR dropping a lot?

i started having that problem with my H10 which had been problem free for a number of years. I don't know where the issue originated from but bought a Garmin HRM+ and the problem is resolved.

I own two H10. I have observed the same behaviour. After the original battery, the one that came with the device, is exhausted and changed the dropouts begin. After the first one I have thought that maybe I have done something wrong so I took great care when changing the battery. No luck. I am using only good brand batteries and I am avoiding the "bitter" ones. In my case I do think that the problem is related to Polar and not Garmin (as much as It pains me to not be able to pin the blame on Garmin).

Usually, when this happens to me, I try:

- Change battery

- Make the band wet (in winter, maybe I don't sweat enough, and there can be drops even mid-run). If that doesn't help, you can try to apply ultrasonic gel (doesn't cost much, helps A LOT) on the band, to improve the contact.

- Wash the band well.

- If nothing helps, change the band (it's cheaper than to buy a whole new H10). For me, they last 1-2 years, and after that they need to be changed. I do wash them regularly, but still.

Thank you for the replies everyone.  I will definitely try the ultrasonic gel.  If that doesnt work work perhaps I will purchase the Garmin HRM+.  It does seem odd to me that the dropouts occurred after over an hour of running though.  

I never run outdoors in winter without first smearing gel on the two HRM contact points. If I don't I also have weird signal issues as I don't sweat at all when it gets cold. By the way, it's not actually ultrasonic gel, it's electrically conductive gel used for ECGs 

In my case it is NOT a problem of, or lack of, electrical contact between the strap and body. The first problems started in summer, and regardless of weather after about one hour of running I am wet so that is not it.

I have an H9 and an H10 with the fenix 7X SS v10.43 firmware and not seen any unusual behavior.

I did see something very much like this a couple of years ago where I would have my HR suddenly drop down into a resting range while running. It turned out to be caused by a specific Polar Pro strap and not the H10 sensor. I discarded that damaged strap and haven't had a problem since. YMMV.

My 3 last runs. Fenix 7SS and Polar H10 (original battery replaced few weeks ago).

Polar firmware 3.1.1

Connection type Ant+

Just out of curiosity, are you connected via Bluetooth or ANT? It is known that these two radios behave slightly differently from each other. 

Also, is there a chance that your strap is getting really dry? I've noticed that with my H10, if I wear certain fabrics when it's cold and dry, I get a lot of errant beats detected (Runalyze HRV data from the H10). My theory is that a charge builds up between the fabric and the strap, making beats drop. 

Runalyze is free to view the HRV data and might give you an indication as to what's going on. If you are getting a high PNN50% it's probably time to replace your strap. These straps last only about 6 months when following Polar's cleaning routine. The conductive gels seem to decrease longevity as well. 

Thank you for the reply.  I connect via ANT.  As for the strap getting dry, I really dont know.  I live in Southern Calif so its never really that cold when I run, min temp is around 60F.  If my running shirt is any indication, I know I am sweating so the contact points on strap should not be dry.