FPV - losing the picture

[Stompp]

Hello all!

Been trying to get FPV to work with my P2 but to no avail. My setup is a Phantom 2 with a GoPro Hero 3+ on a Zenmuse H3-3D using a Foxeer TM25 VTx. On the receiving side I have both tried my Fatshark Attitude and an FR632 receiver with a generic 7" monitor.

The FR632-monitor combo works fine with my other drones, as does the TM25 VTx.

I've connected the VTx using the cable provided with the P2. As you can see from the picture I've joined GND and video GND (as per some post I read but can't remember now). I've checked all connectors, the VTx gets powered ok and switching between NTSC/PAL has no effect.



The problem that arises is that when I turn on the GoPro I momentarily get picture but then it goes black on the Fatsharks and the monitor reports no signal. So the channel is correct (other channels gives static) and the there's a signal but the picture is not coming through.

Any ideas welcome. Thank you in advance

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[jason]

Hello all!

Been trying to get FPV to work with my P2 but to no avail. My setup is a Phantom 2 with a GoPro Hero 3+ on a Zenmuse H3-3D using a Foxeer TM25 VTx. On the receiving side I have both tried my Fatshark Attitude and an FR632 receiver with a generic 7" monitor.

The FR632-monitor combo works fine with my other drones, as does the TM25 VTx.

I've connected the VTx using the cable provided with the P2. As you can see from the picture I've joined GND and video GND (as per some post I read but can't remember now). I've checked all connectors, the VTx gets powered ok and switching between NTSC/PAL has no effect.

View attachment 85484

The problem that arises is that when I turn on the GoPro I momentarily get picture but then it goes black on the Fatsharks and the monitor reports no signal. So the channel is correct (other channels gives static) and the there's a signal but the picture is not coming through.

Any ideas welcome. Thank you in advance

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Accept third party cookies

I would suggest that you check to see what firmware the GoPro 3 + is using. If the GP 3+ is a black and the firmware is v3.0 you will need to rollback to v2.0 and the same goes for the 3+ silver as well. Here's a link to older firmware:
Drivers filed under: GoPro HERO3+ Camera Firmware

Now if that isn't the problem then check that the monitor is on the same band and channel as the TX and that both camera/TX are either on PAL or NTSC.

If you power up the P2 without an antenna on the TX it will be damaged. What type of antennas are you using on both the TX and monitor??

 

[Stompp]

Thank you for your input, Jason I build and fly racing drones as well so I do have some basic knowledge of how FPV works

My GoPro is version 1.04. Tx and Rx are both on channel d4 (5800 MHz), but i've tried other channels as well. I've tried with both PAL and NTSC on the GoPro. I have cloverleafs on the P2 and my Fatsharks. The FR632 has a cloverleaf and a patch.

I just tried the workaround mentioned elsewhere on here to power up the P2 and the GoPro with the USB disconnected and then connect it. This gives me the same result as when powering on the camera with the USB connected. I.e. a short moment of picture on the monitor and then black.

I wonder if the firmware could be the issue. Maybe it's worth updating to 2.x (but not 3.x)? Or could anyone confirm if 1.x fw should work with video out over the USB?

 

[jason]

Thank you for your input, Jason I build and fly racing drones as well so I do have some basic knowledge of how FPV works

My GoPro is version 1.04. Tx and Rx are both on channel d4 (5800 MHz), but i've tried other channels as well. I've tried with both PAL and NTSC on the GoPro. I have cloverleafs on the P2 and my Fatsharks. The FR632 has a cloverleaf and a patch.

I just tried the workaround mentioned elsewhere on here to power up the P2 and the GoPro with the USB disconnected and then connect it. This gives me the same result as when powering on the camera with the USB connected. I.e. a short moment of picture on the monitor and then black.

I wonder if the firmware could be the issue. Maybe it's worth updating to 2.x (but not 3.x)? Or could anyone confirm if 1.x fw should work with video out over the USB?

Are you using a gimbal and what make?

 

[Stompp]

I have a Zenmuse H3-3D gimbal.

 

[jason]

Thank you for your input, Jason I build and fly racing drones as well so I do have some basic knowledge of how FPV works

My GoPro is version 1.04. Tx and Rx are both on channel d4 (5800 MHz), but i've tried other channels as well. I've tried with both PAL and NTSC on the GoPro. I have cloverleafs on the P2 and my Fatsharks. The FR632 has a cloverleaf and a patch.

I just tried the workaround mentioned elsewhere on here to power up the P2 and the GoPro with the USB disconnected and then connect it. This gives me the same result as when powering on the camera with the USB connected. I.e. a short moment of picture on the monitor and then black.

I wonder if the firmware could be the issue. Maybe it's worth updating to 2.x (but not 3.x)? Or could anyone confirm if 1.x fw should work with video out over the USB?

Is that a Zenmuse gimbal I see in the photo? Are you using the video feed from the camera to the CAM socket inside the P2 to the TX?

 

[jason]

I have a Zenmuse H3-3D gimbal.

If you are using USB ribbon feed from the camera to the CAM socket and TX you may have a damaged ribbon or even the gimbals ribbon. The only way to trace both ribbon cables is with a VOM that has a continuity ringer. Other than that I would suspect a defective TX as it shut down once it heats up.

The workaround you mentioned was only used for those who upgraded their camera's firmware to v3.0 which caused the USB output not to function. Instead of a workaround rolling back the firmware to v2.0 made the cameras USB output operational again. The problem was caused by GP which they would not admit to doing.

 

[Stompp]

If you are using USB ribbon feed from the camera to the CAM socket and TX you may have a damaged ribbon or even the gimbals ribbon. The only way to trace both ribbon cables is with a VOM that has a continuity ringer. Other than that I would suspect a defective TX as it shut down once it heats up.

The workaround you mentioned was only used for those who upgraded their camera's firmware to v3.0 which caused the USB output not to function. Instead of a workaround rolling back the firmware to v2.0 made the cameras USB output operational again. The problem was caused by GP which they would not admit to doing.

Thank you for taking your time to help me with this, Jason. Much appreciated!!

I'm using the USB ribbon feed but I doubt that any of the above is the issue. If the cable was damaged I wouldn't get any picture at all and I can repeatedly turn the camera on and off (or disconnect / reconnect the USB) with the P2 (and the Tx) staying on and the picture will show up for about a second and then disappear on the monitor. Or am I missing something?

 

[jason]

Thank you for taking your time to help me with this, Jason. Much appreciated!!

I'm using the USB ribbon feed but I doubt that any of the above is the issue. If the cable was damaged I wouldn't get any picture at all and I can repeatedly turn the camera on and off (or disconnect / reconnect the USB) with the P2 (and the Tx) staying on and the picture will show up for about a second and then disappear on the monitor. Or am I missing something?

Intermittents are just that. I spent 20 years tracing circuits and repairing electronic equipment and ribbons can be a problem but then so can flaky TX and it doesn't take long for those to heat up and shut down. Here is a schematic that covers both zenmuse and cam sockets and the video output and ground on the USB ribbon are the bottom two traces.

 

[Stompp]

Thank you for the schematics!! I'll poke the cables with the meter tomorrow. The Tx works fine connected to another drone and I have the same behavior on the P2 with another Tx I've tried so I think we can rule that one out (I hope).

 

[jason]

Thank you for the schematics!! I'll poke the cables with the meter tomorrow. The Tx works fine connected to another drone and I have the same behavior on the P2 with another Tx I've tried so I think we can rule that one out (I hope).

Check the ribbon cable under the tilt motor as that one is close to the ground and can very easily be damaged.

 

[Stompp]

I've verified the connection from the USB to the Tx connector and it's fine. Got signal all the way. Also tested with another Tx (same make and model though). Still the same result.

Today I realized there was some imagery coming through when pausing recording on the GoPro. The procedure goes like this:

0. Setting up and turning on VTx/Rx and monitor.
1. Turning on the P2 and the GoPro (USB disconnected).
2. Start recording on the GoPro.
3. Connect the USB to the GoPro. This results in a brief picture on the monitor (just like in the vid in the op).
4. Pause recording on the GoPro. This results in the sequence below; USB connected msg, brief picture visible, crappy picture and then blackout.

Don't know if this could give a clue as to what is going on.

 

[jason]

I've verified the connection from the USB to the Tx connector and it's fine. Got signal all the way. Also tested with another Tx (same make and model though). Still the same result.

Today I realized there was some imagery coming through when pausing recording on the GoPro. The procedure goes like this:

0. Setting up and turning on VTx/Rx and monitor.
1. Turning on the P2 and the GoPro (USB disconnected).
2. Start recording on the GoPro.
3. Connect the USB to the GoPro. This results in a brief picture on the monitor (just like in the vid in the op).
4. Pause recording on the GoPro. This results in the sequence below; USB connected msg, brief picture visible, crappy picture and then blackout.

Don't know if this could give a clue as to what is going on.

View attachment 85533 View attachment 85535 View attachment 85534

If you use the reply button in the lower right when you reply it will notify me that you have answered my post.

After looking at the photo you posted of how you wired the TM25 I noticed that you combined the video ground to the power ground. Seem to me that manufacturer would not have marked with the TX with separate video or power grounds if both were common grounds. The same goes for the P2s CAM socket if both grounds were common. Try separating them and see what happens.

 

[Stompp]

If you use the reply button in the lower right when you reply it will notify me that you have answered my post.

After looking at the photo you posted of how you wired the TM25 I noticed that you combined the video ground to the power ground. Seem to me that manufacturer would not have marked with the TX with separate video or power grounds if both were common grounds. The same goes for the P2s CAM socket if both grounds were common. Try separating them and see what happens.

Thx for pointing out about using the reply function. I'll keep that in mind.

Been pondering about the GND's too. The TM25 does have two inputs for GND but neither is marked video. I'll dig a little to see if I can find out if one of them in fact is video GND.

 

[jason]

Thx for pointing out about using the reply function. I'll keep that in mind.

Been pondering about the GND's too. The TM25 does have two inputs for GND but neither is marked video. I'll dig a little to see if I can find out if one of them in fact is video GND.

None of the transmitters I've used are marked as this is the video ground as it's taken for granted by what it is placed next to.

 

[jason]

Thx for pointing out about using the reply function. I'll keep that in mind.

Been pondering about the GND's too. The TM25 does have two inputs for GND but neither is marked video. I'll dig a little to see if I can find out if one of them in fact is video GND.

Has adding the ground to the video resolved the problem of no video??

 

[Stompp]

Has adding the ground to the video resolved the problem of no video??

Yeah, and I got magic smoke :/ The VTx has 5V out. The ground pin is of course for that and not for video. So I went back to the original three cable setup (Vin, GND and video) and tried with a spare VTx only to produce more magic smoke

Now I'm afraid I blew something on the main board in the Phantom as well and I don't dare to try a third time. Problem is that if that's the case my skills for verifying if something is broken on the main board are not enough. Unless it's a burnt lead or component visible to the eye.

Guess I hit a dead end *sighs*

 

[Stompp]

Forgot to attach a pic of the burnt VTx. If I can figure out the component and nothing else is blown I may be able to salvage them. Though I don't know if it's worth the trouble :/

 

[jason]

Forgot to attach a pic of the burnt VTx. If I can figure out the component and nothing else is blown I may be able to salvage them. Though I don't know if it's worth the trouble :/

View attachment 85585

As I recall those unit were very inexpensive to replace at least on my side on the pond.

 

[Stompp]

As I recall those unit were very inexpensive to replace at least on my side on the pond.

A new VTx is no biggie. I'm more afraid of having to replace the main board of the P2 :/