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Tello lost wifi connection mid-flight

MapleGoodness

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I was helping a co-worker set up a new to her Tello this morning in the office.

She was up and flying and then mid-flight, lost Wifi connection to the drone. I think it was due to interference as it occurred directly under a wifi antenna for the office building.

At that point the drone just hovered, and she had no control.

We tried going into her phone settings and reconnecting to thre Tello wifi, which then showed as being connected, but in the Tello app, there was still no connection.

After a couple minutes of fiddling with the phone and Tello app trying to regain connection, I finally, carefully, caught the hovering drone and powered it off.

My question is... what is a person *supposed* to do in this circumstance to regain control of the drone? What if it happened to be hovering 10 feet off the ground, I wouldn't have been able to catch it.
 
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Can't recall if we tried restarting the app.
In theory though, it's possible to reconnect mid-flight?
And re the drone lowering, it definitely didn't for us... But maybe that was because we were trying to reconnect.
 
A tello will normally follow this emergency procedure 50s after the last contact with the phone.
But since you tried to reconnect you most likely re-triggered the 50s delay over and over .

Restarting the app doesn't do any harm but also rarely solves this issue.
 
Thanks for the info, all.

Still trouble shooting the problem for my co-worker.

She took the Tello home, and had the same problem there... OK until the Tello was about 5 meters from her, then the connection dropped... the Tello app view just goes black (the camera view goes black... the rest of the app still shows on the phone) , shows no battery, going into Settings on the app shows no wifi, etc... though it doesn't show any error messages at all... just ... flying normal, then the camera view goes black, and no control, drone just hovers in place.

So, our guess that the problem was flying too close to the office wifi antenna, wasn't the case.

This time at least, the drone did, after a delay, drop to just above the floor.

And after a few moments, despite the camera view still being black on the app, she was able to land the drone.

Not sure if it's her phone dropping connection, or what.

Going to try having her "forget" other local wifi on her phone, to see if maybe her phone is automatically connecting to other wifi, and dropping the Tello....?
 
try another phone to narrow down the possible cause
Tried with my phone and had no issues. Hers' was disconnecting.

Think we narrowed it down to her phone automatically dropping the connection due to it not having internet.

Found a setting to tell her phone to stay connected regardless, and she'll give it a try over the weekend.
 
I was helping a co-worker set up a new to her Tello this morning in the office.

She was up and flying and then mid-flight, lost Wifi connection to the drone. I think it was due to interference as it occurred directly under a wifi antenna for the office building.

At that point the drone just hovered, and she had no control.

We tried going into her phone settings and reconnecting to thre Tello wifi, which then showed as being connected, but in the Tello app, there was still no connection.

After a couple minutes of fiddling with the phone and Tello app trying to regain connection, I finally, carefully, caught the hovering drone and powered it off.

My question is... what is a person *supposed* to do in this circumstance to regain control of the drone? What if it happened to be hovering 10 feet off the ground, I wouldn't have been able to catch it.
What if you were over water like I was with my Spark … 💦💦💦💦💦💦💦💦💦💦 goodbye Spark..
 

I’ve experienced something similar.
I ran a few test flight and this happened once. Video and control was lost also mid flight well within range of wifi coverage as you can see in the video.

I was lucky that this happened when it was only 6-7 meters off the ground. It was a windy day and I kept the drone closer to the ground to mitigate risks of drifting off.
TL-WA820RE was the extender I used , also it’s propped up with a tripod to get some distance off the ground.

What’s the fastest way to re-engage control? As far as auto join is concerned, it’s enabled on my iOS. I ended up having to grab the drone with my hand with the propellers still armed. The spinning propellers whacked my finger. Ouch 😐
 
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You seem to have a fairly long iframe period. Longer than appropriate for the amount of interference
 
What I tried to say is that this looks like a video stream corruption due to interference. Once the stream is corrupt the video becomes pixel garbage until a repair process is initiated.

The repair is triggered through 3 methods:
1) If a corruption is detected the system will automatically initiate a repair.
2) after the iframe period has passed without a detected corruption the system will also trigger a repair (just to ensure that this pixel garbage doesn't stay there forever)
3) manually. If you enable the "Show video stream corruption" setting you will see the bitrate on the screen. If you run into this long lasting pixel garbage problem (due to a very long iframe period) you can tap on the bitrate display and the stream will be repaired.
 
Thanks for the tip. I’ve purchased the iOS version and tried to look for the “show video stream” indicator but did not find it. It’s not under video settings or misc. Maybe something to add in a future update perhaps.

Meanwhile I’ve been taking the time to reading the older threads from 2019 - 2020 on the wifi extenders. I’ve followed Raul’s tip on putting video bitrate to 1MB and iFrame to off. I’d expect 0 and off to mean the same thing since he actually put it to 0.
 
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The lowest available setting gives stable video but lousy quality.

The highest setting (with the maximum being "off") makes a fragile stream that is easily breaking - but with best quality (for the chosen bitrate that is)
 
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