Lost GPS (Merged)

[exfirepro]

Thanks Alex,

There seem to be an awful lot of PFLAA and PAWRT messages compared to the number of GPS messages shown, though I am looking at the log 'manually' so haven't looked very far through it so far.

I will ask Lee to take a look as he can analyse it much more efficiently and I know he will be very interested to see what is going on.

Regards

Peter

[Admin]

Taking a look now.
I will replay to skydemon see if it shows anything.

Alex, FYI you could also try this.

1. unplug the SDR dongle
2. go to http://192.168.1.1
3. select the track in question 2018-01-19_14-00.trk
4. click play
5. connect skydemon

watch to see if SD drops out ...

Thx
Lee

[Admin]

Hi Alex,

I think Paul Sengupta raised a valid point.

Whilst rerunning your tracks, I was surprised to see A/C picked up greater than 240km WOWWWW
What is your antenna setup ?

A highly tuned setup can result in many contacts sent to SkyDemon, and I  have shown that in some tests I can cause an overload somewhere in the system - not sure if that is SkyDemon or the networking.
In the release after 20120721, there is a limit to the number of contacts (I think it is set at 32 closest),
I have seen at one point 49 contacts passed to SkyDemon.

thx
Lee

[a.alexeev.p]

One more track: GPS loss happened while stationary at hold ie after starting moving but before takeoff https://www.dropbox.com/s/9vm1rdfw13ibx6v/2017-12-16_09-06.trk?dl=0

[Admin]

One more track: GPS loss happened while stationary at hold ie after starting moving but before takeoff https://www.dropbox.com/s/9vm1rdfw13ibx6v/2017-12-16_09-06.trk?dl=0

Hi Alex
I have sent you a PM

thx
Lee

[a.alexeev.p]

Hi Alex,

I think Paul Sengupta raised a valid point.

Whilst rerunning your tracks, I was surprised to see A/C picked up greater than 240km WOWWWW
What is your antenna setup ?

A highly tuned setup can result in many contacts sent to SkyDemon, and I  have shown that in some tests I can cause an overload somewhere in the system - not sure if that is SkyDemon or the networking.
In the release after 20120721, there is a limit to the number of contacts (I think it is set at 32 closest),
I have seen at one point 49 contacts passed to SkyDemon.

thx
Lee

Thank you for the reply:)

so set up was:

 I had a GPS mouse plugged in (instead of the default dongle). GPS Mouse and the device with dongles themselves were on the dashboard of PA28 with clear view of the sky. Attached to recommended anker powerbank and PAW supplied power cable. Antennas first two times standard set up as supplied out of the box, second time I put the big antenna on extension lead.

-SkyDemon
- Mode C/S Enabled +/- 2000
- Short Range
- Mode C/S+Filter Beta
-Audio cable was plugged in to my headset
-Version 20170721


Also, I tried to play one of the tracks yesterday- the one from December 16 and unless I terribly lost concentration - it seemed all ok, no interruption noted and yellow aircraft was always seen in SkyDemon. Are you saying it should not have picked up aircrafts that far away? But the new software update not available yet?

[Paul_Sengupta]

The other thing about losing contact on the ground before starting is that other Wifi networks may be present on the ground, and the tablet may be temporarily "distracted" in looking for a Wifi connection with a backhaul of internet rather than the PilotAware, or just scanning around other available Wifi connections.

"GPS" issues are rarely actually GPS issues, more to do with the Wifi connection or rather the "connection" somewhere between the two bits of software, mainly Wifi.

[Admin]

https://support.apple.com/en-gb/HT202831

Alex
Do you have “auto join networks” enabled ?
Thx
Lee

Ps another interesting article
http://www.redmondpie.com/how-to-set-wifi-priority-in-ios-for-iphone-and-ipad-to-get-best-wireless-performance/

[a.alexeev.p]

https://support.apple.com/en-gb/HT202831

Alex
Do you have “auto join networks” enabled ?
Thx
Lee

Ps another interesting article
http://www.redmondpie.com/how-to-set-wifi-priority-in-ios-for-iphone-and-ipad-to-get-best-wireless-performance/

I got "Ask to Join Networks" DISABLED which is described as "Known networks will be joined automatically. If no networks are available, you will have to manually select a network"

That was one of the concerns potentially, but the thing is the problem occurred only inside aircraft with 3-5 maximum conflicting networks (eg my mobile phone and passengers'_ but NEVER when tested at home where we get same 3-5 networks plus another 20 from nearby flats...

[Admin]

https://support.apple.com/en-gb/HT202831

Alex
Do you have “auto join networks” enabled ?
Thx
Lee

Ps another interesting article
http://www.redmondpie.com/how-to-set-wifi-priority-in-ios-for-iphone-and-ipad-to-get-best-wireless-performance/

I got "Ask to Join Networks" DISABLED which is described as "Known networks will be joined automatically. If no networks are available, you will have to manually select a network"

That was one of the concerns potentially, but the thing is the problem occurred only inside aircraft with 3-5 maximum conflicting networks (eg my mobile phone and passengers'_ but NEVER when tested at home where we get same 3-5 networks plus another 20 from nearby flats...

Hi Alex
Unfortunately the method by which it scans and selects alternate networks is quite complicated (if you take a look at the link I supplied), it would be interesting to see the effect of enabling "Ask to Join Networks", to see if this could be an issue
Thx
Lee

[a.alexeev.p]

will do thank you!

[Seanhump]

Evening all ..

My 2p's worth on this subject too ...

I had 'similar' issues today whilst airborne (I took the PAW/ipad min with me to test, with my normal ipad setup for 'skydemon only' use with a BadElf Lightning GPS being used for live navigation)

The PAW did have a few drop outs enroute - I have a second ipad mini hooked up to the PAW unit, and with SD running it would loose the GPS signal at irregular intervals (this happened most of the way from Nottingham to Sherborn). After a fuel stop, the second leg (Sherborn to a private site near Tenby) saw me just using the ipad mini on the Radar screen via Safari (and toggling back and forth between the main screen & traffic screens on separate tabs) - this time there appeared to be no drops in communication.

I left things as they were for the return journey (Nr Tenby back to Nottingham) and the radar screen stayed 'online' and displayed mainly airline traffic all the way back - the odd switch to the traffic screen showed traffic with mode C & S as expected

I'll do some more testing over the next few days and report back (as per previous posts, testing on the ground doesn't throw up any SD GPS disconnects too ...)

[a.alexeev.p]

Evening all ..

My 2p's worth on this subject too ...

I had 'similar' issues today whilst airborne (I took the PAW/ipad min with me to test, with my normal ipad setup for 'skydemon only' use with a BadElf Lightning GPS being used for live navigation)

The PAW did have a few drop outs enroute - I have a second ipad mini hooked up to the PAW unit, and with SD running it would loose the GPS signal at irregular intervals (this happened most of the way from Nottingham to Sherborn). After a fuel stop, the second leg (Sherborn to a private site near Tenby) saw me just using the ipad mini on the Radar screen via Safari (and toggling back and forth between the main screen & traffic screens on separate tabs) - this time there appeared to be no drops in communication.

I left things as they were for the return journey (Nr Tenby back to Nottingham) and the radar screen stayed 'online' and displayed mainly airline traffic all the way back - the odd switch to the traffic screen showed traffic with mode C & S as expected

I'll do some more testing over the next few days and report back (as per previous posts, testing on the ground doesn't throw up any SD GPS disconnects too ...)

Thanks a lot for this! Yes, please keep us updated, but do I understand correctly that so far it seems like skydemon is most likely to be the problem?

[Seanhump]

Not sure if SD is the issue to be honest, hence the need for more testing

I'll also put my PAW back to it's default config too - I'm also using the 'external' mouse GPS (VK-162) and the Nooelec Nano 3 with a tuned 1090 antenna, all wrapped up with the power source in a small enclosure.

I'm going to revert back to the out of the box setup and see if that's any better, just in case the changes have introduced any issues ...

[Ian Melville]

Sean and Alex, are you having to reconnect the tablet/phones to the PAW Wi-Fi?

Or do you just restart 'Go Flying' in SkyDemon?