Mio Link Antenna Problem


I wanted to post some insight I have gained on why so many people are having troubles with the Bluetooth Low Energy connection with the Mio Link.  As I posted in my Mio Link Vs. Rhythm Plus Blog - In my testing at Scosche we measured the outdoor line of sight wireless performance with the following results –

Mio Link = 89 feet

Bluetooth Smart Chest Strap = 209 feet

Scosche RHYTHM+ = 319 feet

After reading some of DC Rainmakers comments in his Blog (over 915 as of now) about the Mio Link it seems there are plenty of users that are having difficulty with Bluetooth disconnects and range issues with the Mio Link.  So, I did some more testing and discovered that the Mio Link is behind the curve and is an unusable device for tracking heart rate. 

Mio Link mountain bike ride with Digifit iCardio App.  Flatline = Bluetooth disconnect.

Another Flatline bluetooth disconnect with Mio Link.

After speaking with the engineers at Scosche whom I’ve been testing the Rhythm Plus for from inception, I have been told and now shown there are clear hardware differences between the Rhythm Plus and the Mio Link - Specifically in the Antenna design.  Here are side by side the antennas of the two products.  In general antenna design, size matters and the larger the pcb footprint for the antenna, the more efficient and stronger the transmitted signal will be. 

When you take the hardware apart, you can see a clear difference in the pcb footprint of Bluetooth antenna between the Scosche Rhtythm+ and the Mio Link.  This could account for the poor performance of the Mio Link. 

Clearly the Rhythm Plus is superior in Antenna size and if you read the DC Rainmaker blog comments, you can see Mio did one more thing to shoot themselves in the foot for design of the antenna – they turned the power DOWN to save battery life.  Therefore - a smaller sized antenna + lower power through the antenna = weak signal = poor performance.  Pretty simple. 

In addition, you will notice on those screenshots above that once the Mio Link disconnects it doesn't re-connect.  During our range testing once the Mio disconnected and went out of range, moving back into range wouldn't reconnect to the device.  You might need to power cycle the armband and/or kill the app to reconnect with the phone.  By contrast, the Rhythm Plus immediately reconnects every time it is within range.  A much better experience for your workout. 

This testing is confirmation to me that all the testing I have been working on with Scosche is paying off.  I have been having a really great experience with the Scosche Rhythm + using both my ANT+ Garmin Edge cycling computer on the Mountain bike and the Digifit iCardio App on my Android Phone. 

I believe in the Rhythm Plus’ accuracy and usability for heart rate training and I NOW have Re-Flashed units for sale on my webstore – Use Promo Code “Rhythm” for free shipping.  The Re-flashed units have fixed the bug for low calorie numbers using ANT+ devices. 

Have you had problems with your Mio Link?  Let me know in the comments.  Also, have you tried the NEW Scosche Rhythm Plus?  Leave me your thoughts below!

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