Lost GPS (Merged)

[a.alexeev.p]

Had same question regarding forwarding... probably not except you can a) may be edit the track and delete the beginning? b)make it play when you are not watching but do screen recording if your device and your nerves are ios11 capable

yes, issue seems different and the extension cord for GPS should have solved it though.. weird.. for me I have been with GPS mouse when the other "original" issue kept coming up

[Seanhump]

PAW as fixed to the rear of the RAM mount

GPS is vertical when mounted and has unobstructed view as its mounted on the inside of the canopy

[Ian Melville]

Hi Sean

Today, I took the Air up and had SD sat there during a training sortie - no disconnects wifi wise, but at least 3 "Lost GPS" messages appearing in SD (in the big green box across the top half of the display). This is with the PAW back in it's "As delivered" config

OK, this is a different issue, this means the GPS really has lost a lock, and is telling SkyDemon it has lost a lock. This is different to a WiFi drop which is a communication loss.

Sorry Lee, I disagree. I have had these dozens of times and the GPS is as happy as Larry, what is not happening is the reception of the UDP packets by the tablet. This is either because they are not transmitted, or they are being swamped by other radio noise. The tablet will remain connected to the Wi-Fi hotspot but hear nothing. This prompts SD to issue a 'Waiting for Device' message. If this continues too long SD drops its flight. I do agree that the loss of Wi-Fi connection is most likely a different issue.

[Admin]

Hi Ian

The reported message was lost gps, not waiting for device

There are 2 possible conditions,
sending and receiving  gps messages containing invalid gps messages
Or, no reception of gps messages
The former causes a pause, the latter a disconnect

Thx
Lee

[Ian Melville]

Sorry, My misunderstanding.

I assume then Sean is getting 'GPS Signal Lost 0 Found'?

[Seanhump]

Sorry, My misunderstanding.

I assume then Sean is getting 'GPS Signal Lost 0 Found'?

Yesterday, yes.

Monday was a complete drop out of the wifi signal.

The tracks saved down on the PAW are split into 3 sections for Mondays flight (flight time was a little over 3 hours) - I know 2 of those were me power cycling the PAW as it wouldn't reconnect.

Wind has stopped play today, should be back up in the air tomorrow and will carry on testing.

The PAW was in the enclosure shown below (the Pi was removed from the stock black case). The mesh across the top is thin aluminum (for cooling) , the rest of the case plastic. All components / cables are very secure when the Pi is in place on the stand-offs. The ipad mini is attached to the case lid via another RAM cradle that's bolted to the lid, giving me a pretty much self contained unit (P3i antenna has been removed on the pic to be re-fitted to the original setup)

[Admin]

The tracks saved down on the PAW are split into 3 sections for Mondays flight (flight time was a little over 3 hours) - I know 2 of those were me power cycling the PAW as it wouldn't reconnect.

Hi Sean
if there are 3 sections, then that means 2 reboots as you say.
Can you supply a spec of the power supply you are using - I am not familiar with that
could it be using any 'soft start' technology on current draw ?

Thx
Lee

[Seanhump]

Hi Lee

I use Dell Power Companions (the 12000mAh ones)

http://accessories.us.dell.com/sna/productdetail.aspx?c=us&l=en&s=dfo&sku=451-bblz

USB Output is 5v, 2.1a

No issues with power during testing or prior to this ...

Cheers
Sean

[exfirepro]

PAW as fixed to the rear of the RAM mount

GPS is vertical when mounted and has unobstructed view as its mounted on the inside of the canopy

Sean,

That could be an issue - the Ublox GPS(s) work much better when the gps antenna (which lies flat on the PCB under the 'black-printed' side of the UBlox dongle) is horizontal. In your other setup, the Mouse GPS is mounted pretty much level as I understand it.

Regards

Peter

[Seanhump]

That's correct Ian ...

Further testing has shown that the GPS works best (for me anyways) when it's not in close proximity to the Ipad ...

Current setup has the PAW strapped to the back of the RAM mount, which in turn is suckered to the canopy. (This 'sort' of makes sense - the PAW in the enclosure has an external mouse type GPS, but also has an ipad mini fixed to the enclosure lid - prior to trying it in flight, all testing was done with the lid / ipad  separate ...)

Moving the GPS away, if only by a foot or so, improves the situation and results, so far, in only one 'lost GPS message in SD.

More testing on the ground has confirmed this (the UBlox 7 is also flatter when on a USB extension so that may / may not assist things.

My GPS 'Mouse' has had its cable shortened for use in the enclosure, so another had been ordered (with the 2m cable) to see how that fares ...

More in the air testing to be done (along with 2nd ipad running EVFR) on Sunday - it'll be an easy day with no Nav kit needed so if it does prove to be a problem still it won't be an issue ...

Wifi wise, things seem to have been fine so far - I'm wondering if the enclosure, with the very close proximity of the batter pack / cables and aluminum vent along the top was causing problems (it's an in-shielded plastic case so you'd think it'd be fine)...

[Paul_Sengupta]

Ah, this is something we figured out a while back with the Wifi and it's why you can select the power, standard and channel. You can't have the PAW and the tablet too close together. At one point in the early days, my tablet would only work between something like 60cm and 2.5 metres from the PAW...any closer or further away and it wouldn't work.

These days, on the lowest power, it works down to about 6 inches from the PAW. But I think for reliability it would need to be at least a foot or two away.

[Seanhump]

Ok ... that helps

I think I'll grab another RPi (already have the Nooelec ADSB dongle and GPS Mouse) and do some separate testing without the ipad mini on the enclosure, and keep any eye on distances to the device running SD

Does anyone know if the separate bridge that's offered for sale comes with the P3i antenna

I assume I should be able to use the 28 day demo key for testing ..? - no point having two licenses!!

[exfirepro]

Paul,

I missed that one! Extremely close proximity could potentially create a screening situation, where the case of the pad blocks the WiFi signal. I certainly used to get obvious screening if I ran a FlarmMouse with its standard antenna ‘behind’ the iPad, so now use a remote antenna. When I’m running my PAW in the car (during testing) the PAW and iPad mini are about 6” or so apart and that seems to work OK with the default WiFi settings.

Regards

Peter

[Paul_Sengupta]

It's the same with a plastic cased tablet. Wifi connections don't like being too close together in my experience. I'm guessing it's something to do with power control and swamping, though it's only a guess.

[a.alexeev.p]

Ok, so today and yestetday for the first time the issue repeated when at home. Confirmed from home page that the device did not reboot. Potentially, looks like the problem indeed might be in nearby wifi devices, but no real evidence to confirm that yet... in theory having everything else around on flight mode might help