CPE.bin

[ewald.gruen]

After having collected more than 500 km of traces with the 65s and more than 100 km with the 66sr I can say with a very high confidence that the 65s has a slight advantage over the 66sr - especially in challenging terrain. However, the difference is likely small enough to make it irrelevant to a buyer's decision-making process.

[GPSrChive]

Our 65s loses about 80 % of satellite signals any time it is not held perfectly vertical, and our 66sr does not regardless of orientation.

Based on the hardware we have, the 65s is inferior to the 66sr.

[ewald.gruen]

I've had my 65s mounted horizontally on the handlebars of my bike for the past three weeks, and it has performed just as well, if not better, than when I've held it vertically while walking or running, and certainly as well as the 66sr with the same handlebar mount.

Here are two charts from today (with the 66sr) and yesterday (with the 65s) on almost the same route with both devices mounted exactly the same way:

• 65s (3.5 % error):
  65s_speed_comparison.png
• 66sr (4.6 % error):
  66sr_speed_comparison.png

The antenna orientation has zero measureable effect on the quality of the recorded traces on both the 65s and the 66sr.

[GPSrChive]

In your two examples, you are measuring the GPS calculated speed for the GPSMAP 65s and GPSMAP 66sr vs the Speed Sensor 2 reported speed to state one has more error than the other. This of course assumes the Speed Sensor 2 always has zero error. So, for now, it really should just be called 'Speed Difference', not 'Speed Error'.

Without seeing the actual non modified track logs from each device, it is impossible to determine why there is a small difference in reported speed between the two GPSMAP devices. Any number of variables can contribute to this, including the frequency and timing of recorded track points. Assuming that both devices recordings were recorded simultaneously, and both are equal in length, the total time for each should also be equal, and the speed variations should average out to zero. Again, without seeing the actual recorded track logs...

With the Satellite Page open on your GPSMAP 65s, held vertically and slowly rotated into horizontal (face up) orientation, you do not see the satellite signal bars drop significantly? Every other person I know that has a GPSMAP 65s observes this same behavior.

[luvvinbird]

But does it affect accuracy if the "bars" shrink a bit in horizontal mode and lengthen when held vertically? My 65s always shows 6ft accuracy regardless of the way I hold it. In fact, I'll swear after playing around with it long enough, I had the Glonass sat bars doing the opposite, lol.

[luvvinbird]

I fully agree that some of the 66sr's firmware bugs are are major pain in the ass and that Garmin is either lazy or simply unable to fix these issues themselves, but still, I can't complain about the accuracy of the device - even though I'm pretty sure by now that the 65s is superior in terms of accuracy - but I can't tell if this is due to differences in hardware or software or both.

... the longest being Galileo which comes well after Glonass and GPS.

Which is indeed a shame.

I couldn't agree more. I don't own a 66sr but I want to. I'm waiting for a fix on those PITA problems before I shell out the $700 (CDN) to buy one. I just can't see how superior it is to other handhelds with those issues unresolved.

[mimichris]

Following this CPE and multi-band problem, I think the 66s is just as good without having this CPE update inconvenience, I had one in 2018 which I sold, I don't remember why actually.
I chose the 66sr for multi-band and I'm a little disappointed....But now that I have it I'm keeping it hoping Garmin improves it.