Thread: About 37xx converted to 34xx satellites reception accuracy

Originally Posted by lolypop000

I think that we found something out from this.
1.) If you don't have rxn folder and inside poly, seed, eph, pred then accuracy is bad.
2.) If you remove Arc.bin, Bee.bin and mt.nvm, create procedure for satellite and then nuvi makes these files by himself then you have better accuracy
One of this two is correct, but which one
p.s.
If i remember correctly Caty have rnx folder and bin files from the beginning and have good accuracy.
I think that solution for good accuracy is rxn folder, but we must whait for sig to test and report.

The next tests results:
1. It is clear that my Nuvi 3790T -> 3490 has better accuracy when I’m not in a move. It is about 4-6 meters.
2. City drive test – accuracy between 10 to 21 meters. Average accuracy 14-18 meters.
I have started with accuracy of 6-7 meters /car moves up to 20 kmph/, but as soon as I increased the speed, accuracy changed fast to worse. As you can imagine I tried to evaluate the reasons behind accuracy drop down. As far as I can recall now there are several reasons besides flashed Garmin firmware:
- No good visibility to satellites, caused by
a. buildings – I’m living in relatively small town with no very high buildings
b. trees – not much, at least it is winter time
c. bad weather – cloudy, but not bad
d. Roofs - non
- Strong magnetic fields – no
So more or less I have had normal city drive conditions.
I have noticed that my unit improved its accuracy, signal strength respectively, when its back side is faced to the sky. Signal strength improves with more than 15-25%. Most probably it is connected with antenna and for test purposes the unit was in most favorable position for good signal reception.
The first conclusion was – more speed – worse accuracy. I was not convinced and…
3. Disappointed by first results of city driving, left the town to nearby village just 15 km. away.
On the Stop sign in the end of the city I have checked accuracy 10 m. In the open areas without no trees and flat terrain the accuracy was between 10 and 12 meters. Speed varied between 90 and 130 kmph. So far, so good. I was wrong about the speed. When terrain changed – heights on the right side, accuracy dropped to 15-22 meters. Average accuracy for my outside city test – 14 – 17 meters. Average speed – 100 kmph.
These are the results.
Then stopped and go out of the car – again 4-6 meters accuracy. In stopped car – not less than 8-9 m.
My conclusion – despite improvement, the unit reception is not stable and its accuracy is too much voluntary. There were no change in any of the new files in rxn dir after the test. MSL_log.txt size is 0. No such a file like Dasilvarsa mentioned 36 rxn_config_.
@ Caty – when rxn dir showed up in your unit or it was there already when you bought it?