Skyplot legend

[moltob]

Hey,

being a new locusmap user (coming from Komoot) I am blown away by the app. What an excellent job of balancing feature richness and usability. Great docs, too.

Ok, now I do have a question, which I did not find answered in the docs or the forum or elsewhere.

Looking at the GPS skyplot I was interested in what the different icons and colors mean exactly:

• Color of satellites/signal strength bars: What exactly do the thresholds between the colors mean? How bad is red? I don't think I have ever seen green so far, should I?
• Shape of the satellites: What does square vs. circle mean?

Hope I did not miss the obvious...

Thanks a lot,
Mike

[Menion]

Good day Mike,

I'm glad you like that app and I'm sure that @Michal will be glad you like the docs!

Seems that docs will need some improvements ( http://docs.locusmap.eu/doku.php?id=manual:user_guide:tools:gps ).

Meanwhile: the height of bar is based on "signal to noise ratio" value. Exact values are not important anyway green value is reachable but only in really really good conditions.

Shape: circle symbol means satellites from Russian Glonass systems, square share are currently all other GPS systems (in most USA GPS).

[Andrew Heard]

Good questions, I've never seen description of skyplot icons either.

[Michal]

Thanks all, I'll look into it

Odesláno z mého MI 3W pomocí Tapatalk

[Menion]

Before publish in manual. Pse double check.
The encircled ones are gps ?  Square ones glonass ?

Willy thanks!

Double checked, and sorry.

Correct answer:

- square symbol => satellites from Russian Glonass systems
- circle symbol => currently all other GPS systems (in most USA GPS).

[balloni55]

i´m an old locus user (in a double sense) and infos in skyplot window are also partly unclear for me

i know:
- count of numbers under receiving strength bar are visible sats
- count of green numbers under receiving strength bar are used/fixed sats

btw @ Michal, in manual it´s declared vise versa as it is displayed > number of visible/fixed sattelites and spelling mistake "satellites"

now  questions to my screenshot:

# 18, red dot > used ?
# 33, 38, good strenght > not used ?
# 68, red square, no strenght > used ?
# 69, 74, green square, good strength > not used ?

and why ~50% of glonass sats with good strength are not used ?

[Michal]

Typo fixed, thanks. Other questions are for Menion, I myself don't know the answer.

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[Menion]

Ah forgotten topic, sorry ...

Algorithm on background is quite complicated. I remember that I've computed some simplified versions with 4, 5 satellites on university. There all satellites were used in final compute. Just some gave very inaccurate values compare to computed value (big deviation) so their influence on final computed value was low. And I think here it is really similar.

You have to remember there are two different values. Strength of signal and deviation from computed value. Even if signal may be strong, this do not guarantee that deviation will be low and of course opposite. So you cannot simply say : good signal > have to be used.

And why Glonass satellites are used less time > don't know as well. These satellites has global coverage similar to USA GPS. Maybe chipset in your device works better with USA GPS. Better ask Google & device manufacturer (I know, impossible task).

[balloni55]

Hello menion
thanks for your honestly answer

[abwinston@gmail.com]

What do the asterisks mean on the satellite-strength bar chart?

[Menion]

Good question, thanks, seems that the asterisk is missing even in updated manual for the Locus Map 4.

With this symbol are marked satellites that communicate on two frequencies. Modern devices allow to use of so-called L1 and L5 wave-lengths. This simply means a lot higher accuracy.

Notification to @Michal , please update the manual, thanks.