Had the same thing happen as well. Saw the "Signal Lost" message yesterday. Updated to the latest firmware and flew this morning. Was airborne a few minutes before I noticed the "Signal Lost" notification again. Still had full control of the Phantom though. Each time I brought it back and landed, restarted the dji app, and everything was then fine. App glitch? Can be unnerving...
My Phantom 3 Pro showed "Signal Lost" with full signal and control
- Thread starter VoicOfReason
- Start date
I had the same "Signal Lost" no matter what. Sometimes it happens. Just stay calm and do RTH only if you see it, other wise wait and slowly move left right untill signal shows up
Same thing happened to me today. I've had awful wireless video signal since the firmware upgrade as well. **** near unusable. Using a P3P with HTC One M9.
Could everyone explain there surrounds when this stuff happens.
Are you in a residential area?
Commercial?
No one around but you?
Close to the car?
Did you empty your pockets of other electronics?
Try and remember that stuff if you can.... Facts like that start adding up to possible solutions too.
I think everyone should download a Wifi Analyzer and check the 5 and 2.6ghz activity when this stuff happens too.
They are free work great and IOS or Droid.
Just my $1250.00 dollars worth
All right 5 Cents worth.
Are you in a residential area?
Commercial?
No one around but you?
Close to the car?
Did you empty your pockets of other electronics?
Try and remember that stuff if you can.... Facts like that start adding up to possible solutions too.
I think everyone should download a Wifi Analyzer and check the 5 and 2.6ghz activity when this stuff happens too.
They are free work great and IOS or Droid.
Just my $1250.00 dollars worth
All right 5 Cents worth.
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Seafront at the top of a steep incline, buildings around 100m behind me.
Many people watching possibly around 15-20
6 feet or so infront of cars parked on the side of the road
No other devices apart from the phone connected to the controller - Adam
For anyone that hasn't read the other numerous posts about losing video signal, rebinding the controller works most of the time. I had the same loss of signal when I first received my A and rebinding the controller fixed it immediately. It's completely feasible that whatever is happening under the hood during a FW update might touch/tweak/reset the code that controls the LB chip. It should literally be the first thing to try when experiencing dropping/choppy signal.
No, but doing so before flight will likely fix the issue for the ensuing flight. Worked for me, anyway.
Residential area, a few hundred feet up, about 1/2 mile out, wifi/bluetooth disabled on Nvidia Shield Tablet. "Signal lost" did not vary. It did not fluctuate. It started at 1/2 mile out and stayed on all the way until I landed and walked up to it and picked it up. Even then, the message stuck.
Anyone here understands logs? I had some disconnect yesterday for about 10 secs, at 200M distance, I see the log data on 2 vars is abnormal at some moment and I think thats the moment when my phantom disconnected, what mean these 2? Here are the values :
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Guys, the RF propagation follows some complex rules and that depend on modulation type, encapsulation and protocol used. Adding more, there are RFI (RF Interference) between appliance, chips, boards. Adding more there are other signals more or less powerful, harmonics and so on.
Speaking in term of DJI Phantom 3, when signal drops, you face the following situation, in order of frequency:
1. RF Signal is OK, but not enough information can be decoded from the packets to/from bird. This affect mainly video packet that needs big chunks, preamble, sequencing and checksum. When more than 2-3 packets get scrambled by the receiver the RC loose for an "amount" of time the sync with your aircraft until new key frame packet is regained by the receiver.
2. RFI: some not good quality china-cable microUSB or Lightning, specially if long, can become an antenna itself. If this happen .. ciao ciao decoding. Use RFI inductors on the RC USB side of the cable, making one turn of cable.
3. The bird and RC really get uncapable of syncronize. In this case you are in a "no fly" area due to very high density of other signals. This argument, if interested can be seen a deeper but it's complex.
4. No signal at all or intermittent RF signal between bird and RC. In this case can be fault antenna, PA (power amplifier) not working at correct power, signal destroyed for some reason. For example, never keep hand on the antenna, specially on the metal base ring.
A note on RC/Bird bind: each packet sent by radio RF has a specific structure, which contains many informations, and one of this is a serial identifier for the RC/Bird packet exchange. Well, if for some reason something change this "numbers" in one of the two sides, they can't talk anymore. This can happen (very low probability), but if it happens ALL the packet will be discarded. I don't believe that rebind solve the problem, unless really big mess is happened.
Speaking in term of DJI Phantom 3, when signal drops, you face the following situation, in order of frequency:
1. RF Signal is OK, but not enough information can be decoded from the packets to/from bird. This affect mainly video packet that needs big chunks, preamble, sequencing and checksum. When more than 2-3 packets get scrambled by the receiver the RC loose for an "amount" of time the sync with your aircraft until new key frame packet is regained by the receiver.
2. RFI: some not good quality china-cable microUSB or Lightning, specially if long, can become an antenna itself. If this happen .. ciao ciao decoding. Use RFI inductors on the RC USB side of the cable, making one turn of cable.
3. The bird and RC really get uncapable of syncronize. In this case you are in a "no fly" area due to very high density of other signals. This argument, if interested can be seen a deeper but it's complex.
4. No signal at all or intermittent RF signal between bird and RC. In this case can be fault antenna, PA (power amplifier) not working at correct power, signal destroyed for some reason. For example, never keep hand on the antenna, specially on the metal base ring.
A note on RC/Bird bind: each packet sent by radio RF has a specific structure, which contains many informations, and one of this is a serial identifier for the RC/Bird packet exchange. Well, if for some reason something change this "numbers" in one of the two sides, they can't talk anymore. This can happen (very low probability), but if it happens ALL the packet will be discarded. I don't believe that rebind solve the problem, unless really big mess is happened.
I had this happen to me too! Saw no signal but I had full bars, video stream was good and still had control. However, the no signal message did go away when I started bringing it home.
All the technics and technology involved in data trasmission has the goal of miximize spectrum efficiency, that is to say more speed, less error in a specific bandwith. Now, MIMO is one of the best actual tech in terms of this goal. Every trasmission technics try to bring down the error probability, as a limit to 0, but it's not really a 0 in real world. MIMO antennas works better if far each other (more than 2 lambda, 30cm for 2.4GHZ). That's not pratically applicable in most appliance.
An other note about phone/tablet wifi: WIFI on/off doesn't make any difference, unless a connection is established with an AP. Does matter, instead cell signal, on the 800mhz of some 3G network: the harmonic x3 is going in the RC Band. Remember that cellular tranceiver adapt power to the cell distance, and IF you have very distant cell it will go with max power output !
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Sure, but it's my understanding that Lightbridge uses distinct channels for telemetry and video, so isn't it feasible that you could potentially lose one of the packet streams but maintain the other?
You may be right, but that's not madatory. I don't know which low level modulation scheme lightbridge is using, but for sure it is a QAM type, not far from the dear old 802.11b (11Mbps). Probably this is used on a 2 virtual channel communication, video and control.
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