Garmin Varia RTL510 sending incorrect Target Speed

Clone of https://www.thisisant.com/forum/viewthread/7237/ : No response for a while

Hi Garmin Radar Team,

I am implementing Radar on a Stages Bike Computer and am testing with the Garmin RTL510 Model 2954, HW Rev 51, FW version 3.50 (serial 33000006678). I am noticing that the radar target speed value the sensor is reporting is not correct. It appears to be about twice the value that it should be.


I used an RTL500 and verified that this radar is returning the correct speed.

I verified the results on an Ant simulator also.

Please let me know if the Garmin RTL510 is using the conversion shown on the ANT Radar spec of speedTarget: 1bit=3.04m/s (Range 0-45.6m/s). Document number D000001664

NOTE: I retested with version 3.70 and it looks like the speed value reported is in Miles/hour instead of meters/second as per the standard.

Thanks,
Abid Esmail