Lenovo Tab3 7 connection problem

[Vic]

Watching this thread with interest as I'm still having issues with my Lenovo Tab 3-8 and the latest PAW release. Not just in UDP where the disconnects are measured in seconds but less frequently in FLARM mode too. Strangely though, the last time I flew, my mate connected with his Lenovo Tab 3-7 and that was fine!  Perhaps there's another app I am using that is doing strange things?

Every red dot in this plot corresponds with a disconnect of the UDP...



Oddy, when I connect to PAW on the ground it is not as easy to replicate the problem!

I've even re-fired up my original Nexus 7 with a very stripped down Android build to try next time I fly to absolutely confirm it's not the PAW.

On the good side, we have recently upgraded the comms panel in the C172 with a PAR200A combined comms panel /8.33KHz transceiver which has bluetooth. Hanging a £10 bluetooth transmitter dongle into the audio socket of the PAW, pairing is flawless and the audio alerts are now wirelessly fed into the aircraft comms. 

Just found an app for android called UDP sender / Receiver with which I'll have an experiment later today.

[Ian Melville]

Vic, are you getting any messages flashing up on the SD screen?

[Vic]

Yes Ian, I get the "waiting for device", just like the original poster.

Following on, I've installed a handy little App UDP Terminal  Which when connected to the PAW through WiFi allows me to see the UDP traffic.

I installed this on all three of my devices, Huawei P9 Phone, Original Nexus 7 2012 and the Lenovo Tab 8-3. When set to listen on UDP, on the Nexus and the Phone, there are regular blocks of messages, on the Lenovo it is missing out messages, sometimes for quite a few seconds. This is surely the 'problem' in action.  The question is, why??

Watch this (rather awful and out of focus video, ) The Lenovo is in the middle  https://youtu.be/6JUc7hQXELc clearly it's missing a lot of data! All 3 were connected to the PAW, I changed the wifi connection on the RH Nexus while the UDP app was running so it was titled another SSID

Can a mod please remove the 'solved' from this thread title!

[Admin]

Hi Vic

Great analysis!

From left to right, which is which ?
Also OS releases on each

Also I presume this is using UDP, can you do the same experiment on TCP ?

Thx
Lee

[Vic]

Hi Lee, from left to right..

Huawei P9, Android 7.0
Lenovo Tab 3 8, Android 6.0
Nexus 7 v1, Android 4.4.4 Cyanogenmod 11.0

I'll try repeating with TCP over the weekend and report back.

[Ian Melville]

Hi Lee,
I now have a Lenovo Tab 3 7" and can confirm Vic's experience. I ran the UDP terminal alongside the iPhone running SD and the 'Waiting Device' message popped up several times at the same time on the iPhone as the data stream in UDP terminal paused on the Tab 3. So this is possibly the issue that I have been chasing my kit.

I have also discovered that if you change the PAW network setting to 802.11B, rather than the 802.11G default the messages reduce as do the pauses in data in the UDP terminal. It does not stop the issue. Oddly it looks as if it passes more traffic as well, but that may be a coincidence.

So in summary: I have experienced the issue on
iPhone 5
iPad mini first generation
iPhone 8
Lenovo Tab 3

I get the error messages on SkyDemon and Eazy VFR Basic and see the data pauses or gaps in a UDP port monitor.
We have replaced my entire PAW for known good and used different recommended Anker 12V-USB Power, Anker 10,000mAh and EC Technology 22,400mAh power banks.

This issue has only recently started for me, I suspect when I wiped my SD card and reimaged rather than upgrading using USB. I used to have 802.11B selected from the early days as it gave me the most reliable connection. When wiped, it will have defaulted to 802.11G. Of course, this may be a red herring? It could also be that this hides rather than eliminates the issue.

I was beginning to worry that I was the only one reporting this issue I suspect this is also the same symptoms as reported by Darren. and his co-owner.

[Vic]

Just to confirm that I do also get disconnects in FLARM (TCP) mode, tho far less frequent.

And, like above this has only manifested since the Pi kernel 4 update.

[Admin]

Hi Ian, Vic,

Please post the following information you are using for these tests

1. PilotAware Version
2. RPI OS Version
3. Wifi Mode B/G
4. WiFi Channel
5. WiFi Power

Also if you know what channel your home router is using, that would be useful

thx
Lee

[Ian Melville]

Will do this evening

[Ian Melville]

1. PilotAware Version 20170721
2. RPI OS Version  Model B Pi2, Kernel=4.4.34
3. Wifi Mode B/G Both B and G
4. WiFi Channel 1
5. WiFi Power 1mW and 10mW

Home router is using Channel 1, not that it can see that WiFi network away from home.
I'll PM you further details

[Vic]

1. PilotAware Version 20170721
2. RPI OS Version  Model B Pi2, Kernel=4.9.35-v7+
3. WiFi Mode B  (G seems to make no difference to me)
4. WiFi Channel 9
4. WiFi Power ..Tried all!
5. Home Wifi on Channel 1

[exfirepro]

Curiouser and curiouser! (Said Peter)

It would be interesting to hear any update from Colenso on his experience since changing his Lenovo to FLARM/TCP. Don’t worry about the Technical complications, Colenso, just an experiential update would be useful to add to the pot.

Regards

Peter

[Colenso]

UPDATE

I've managed a couple of flights in recent days. On both occasions I've had both the Lenovo and the iPad connected to PAW. The Lenovo is connected using FLARM and the iPad connected using PILOTAWARE. On the first flight the Lenovo lost the connection between SD and PAW but reconnected within a minute or so. The iPad kept the connection for the whole flight.
On the second flight I noticed no loss of connection on either machine but on examining the log of this flight on both machines I notice what appears to be a loss of connection but at different times. I'm assuming that the red dots on the time line signify a loss of connection. Please correct me if I'm wrong. I've attached two screenshots to show this.
Do you think that the problem is now resolved?

Thanks and best wishes for the New Year.

[Ian Melville]

Colenso,
Do you have a phone or other device that is connected to 3G Data during the flight?

[Colenso]

Hi and thanks for the quick response.

I carry an iPhone 6 in my jacket which presumably is connected to either 3G or 4G.

Will this affect PAW?