GPSrChive Discussion Forum

Dear all,

I have the following problem: It seems that Garmin's heart rate monitors (those with the chest belt) are not compatible with my body any more. I now have tried three of them, have changed the batteries etc. One of them is a brand new HRM-Dual.

I can pair them with the Montana 700, and initially, they obviously recognize my heart rate, and the device shows the heart rate correctly. However, after some time, whether or not I start an exercise, the device either shows no heart rate any more (data field becomes empty), or it shows weird values (usually less than the half of the correct value, but sometimes it's way above the correct value).

In some cases, the respective data fields shows no value and weird values in alternation.

I don't know whether the problem is due to the heart rate monitor or due to the Montana 700. This leads to the first question:

1) Are there known problem in the hardware or software of the Montana 700 which could cause the misbehavior?

Now I'd like to conduct some tests. To rule out the Ant+ part as possible culprit, I would like to pair a heart rate monitor via Bluetooth with the Montana 700. This leads to the second question:

2) Is it possible to use heart rate monitors via Bluetooth with the Montana 700? If yes, how?

The Montana 700 offers to be paired with Bluetooth devices, but as far as I have understood, only with mobile phones or with audio devices.

If I really can't use Bluetooth, there is my third question:

3) Which heart rate monitors (chest belt based) from other manufacturers are compatible with the Montana 700?

For example, I have found two models from Polar which claim to offer Ant+, but both have got a lot of negative reviews, and some people stated they couldn't use them with their Garmin devices because the devices just didn't recognize them.

Thank you very much in advance for any help,

Themistokles

HRM-Dual is ANT+ and Bluetooth, and Montana 7x0 may have paired using Bluetooth. Can you share a screen capture of the sensor setup screen after pairing?

Thank you very much.

I am quite sure that it is paired via ANT+. I can't post a screenshot right now, but if I go into it says (in the first list item) Furthermore, if I go into there are only two menu items:
Therefore, I believe that we can't pair fitness sensors via Bluetooth with the Montana 700. I asked because I would like to be sure, in case I have missed something.

OK, the Montana has connected via ANT+ there.

Unpair, search again, and you should see a screen similar to this:


Select the 'BLE' option to pair via Bluetooth Low Energy.

You will not pair Bluetooth sensors via the Bluetooth Setup Menu, only your phone and headsets.

Actually, now that I think about it, if my memory serves, the ANT+ is always going to be the preferred connection method over Bluetooth, as it is a more robust and reliable wireless protocol. Bluetooth was only recently added to allow their sensors to work with some non-Garmin exercise equipment.

Have you tried a slightly different 'wearing position' other than center chest?

Unpair, search again, and you should see a screen similar to this:

Thank you very much! I would never have come to that idea. But indeed it has worked. The HRM Dual is now paired via Bluetooth with the Montana 700.

Have you tried a slightly different 'wearing position' other than center chest?

Yes, I have, but to no avail.

But in the meantime, I have done a lot of research, and it seems that the Garmin chest belts are having problems in general. This conforms with my own experience: The first one (pre 2013) has stopped working correctly after one year or two, the second one (post 2013) has stopped working correctly after two years. I have tried a third one (bought in 2019) just two days ago, and it failed from the beginning on.

I don't believe any more that the problem is due to the wireless transmission, and don't suspect any more that using Bluetooth instead of ANT+ will solve it.

Well-known DC Rainmaker has written up an interesting summary about the subject.

One of the solutions he proposed seemed weird, but already worked perfectly for me: In addition to the Garmin belts, I also have an old belt from Polar. I could clip the Garmin transmitter onto that belt without any issues, and to my surprise, that combo immediately worked.

Yes, you are reading this correctly. I took my old Polar belt which had been used many years and since then was just lying in a drawer for the same number of years, removed the Polar transmitter from it and mounted the Garmin transmitter onto it. The Garmin transmitter fitted perfectly onto the Polar belt - I didn't need to cut anything (in contrast to what some other people have observed). The Montana 700 had no problem with pairing the Garmin transmitter on the Polar belt, and everything worked perfectly all of a sudden.

Out of curiosity, I also have ordered electrode gel (adhesive type), and will try that with the failing Garmin belts. I don't expect anything from that test, but am curious. I also will wash the Garmin belts (again, but this time in a washing machine) and additionally try to clean them with alcohol.

I can't explain what exactly is the problem with the Garmin belts. With all three of them, I have measured the electrical resistance between the silver electrodes which connect to the transmitter and the plastic electrode pads which are in contact with the skin. The values were similar for the three belts, and were similar to another belt which I had borrowed from a friend and which (currently) works correctly (about 0.8 kOhm).

I also have have stressed the belts a little bit (pulled them at the ends / stretched them, wrapped them around a toilet roll with some tension etc.) while repeating the measurements. Once again, I couldn't notice a substantial difference between the three belts which are failing and the one which works.

It seems that there are some more reputable manufacturers of cheap belts (around 10 EUR) which are compatible with the Garmin transmitters. I've now ordered one of those and will use my old one from Polar until it arrives.

Thank you very much again!

Do you have a link to the third party belt?

There are many, with different availability in different countries, of course. The cheapest offer I have found (2 belts for less than 13 EUR) (dont worry, the page is in English ):
https://www.amazon.de/-/en/Frequency-Re ... B07MCXCJTW
This belt is definitely compatible with the Garmin transmitters.

The following is an alternative from a well-known and reputable brand, and is the one I have ordered:
https://www.bike-discount.de/en/buy/sig ... rtex-54599
I am nearly sure that it is compatible with the Garmin transmitters; "nearly" because I didn't find a picture where the second electrode is shown, but I have been told indirectly that it will work.

Best regards!

P.S. I have found more, but didn't note the sources, because I either would take the first offer mentioned above (if I would be willing to buy a super cheap "pure-Chinese" product), or would buy a Polar Softstrap as an alternative to the Sigma. The reason why I opted for the latter one is just curiosity (now that I already know that my old Polar works ...).

As for the Polar:
https://sportgigant.at/zubehoer-/40967- ... 17761.html
While it is not the one I have (mine is older), it is compatible with Garmin transmitters. In some cases, a part of the plastic / rubber rings around the electrodes must be cut before the Garmin transmitter can be attached and sits firmly, according to user reports. However, my old model does also have those rings, and I didn't need to do anything - the transmitter fitted perfectly and very firmly.

Best regards!

Thank you!

This will provide our readers with multiple potential alternate options should they find themselves experiencing similar symptoms.