Doubt about Suunto 9 Baro altimeter/barometer calibration

Fatih Kale

Hi all,

Yesterday I ran on a track while raining so watch was covered by my jacket.

When I check altitude profile it’s veird. It shows that I went downhill but it’s not possible as I was at the same location turning around. Why could this strange values observed?

Here is altitude profile
link text

Here is the temperature graph
link text

freeheeler

@Fatih-Kale
I’ve seen a similar behavior with my Suunto Core some years ago.
When the sensor is covered or in contact with wet skin it seals off and or has a pumping effect.
I would expect that this wrong measurement is detected by fusedalti, but until today I still don’t understand how fusedalti works in detail and what it does over an entire activity or when for some reason the alti is completely off reality.

sartoric

@Fatih-Kale
Check if you also have some magnetic stuff (like magnetic jacket cuffs)

Mff73

@sartoric said in Doubt about Suunto 9 Baro altimeter/barometer calibration:

@Fatih-Kale
Check if you also have some magnetic stuff (like magnetic jacket cuffs)

For altitude issue? 🧐

isazi

Also if it was raining and there was a storm coming in, or any other air front, and you just came out of your place, the altimeter may be adapting to pressure change.

sartoric

@Mff73
mostly for gps (so fusedalti)

Mff73

@sartoric said in Doubt about Suunto 9 Baro altimeter/barometer calibration:

@Mff73
mostly for gps (so fusedalti)

I didn’t know about GPS issues with magnetic parts Compass OK, but GPS.

sartoric

@Mff73
For sure not the signal , but I won’t discard issues due to components (maybe not directly related to gps) or maybe something related to fusedtrack

In an old topic we discussed about issues with OHR reading due to magnetic interference … or maybe was gps … need to check it

EDIT :
Was fusedtrack (keep asking to calibrate) in that case, don’t you remember ?
https://forum.suunto.com/topic/1371/s9-2-4-14-calibrate-fusedtrack-interface-problem-suunto-case-01853829/100

Brad_Olwin

@Fatih-Kale If the sensor is covered altitude readings can be wrong or distorted. I have this happen when the sensor is covered by a buff as well.

Fatih Kale

Thanks all it was possibly due to sensor was covered.

I had another run last night, this time I strapped watch over the jacket and got correct readings.