FPV problem with GoPro H3 Black

[DaveT1]

I'm having a recurring problem of my GP H3 black failing when used with my Fat Shark Predator. It appears that that the USB port fails and I don't get a signal from the camera to the FPV Tx. I've tested all of the components and everything is working. The cords from the H3 to the FPV Tx are in good shape. I tested them with another H3 white. This is the third H3 Black to fail in five months. GoPro has been great about replacing them, but I would like to get to the root cause.

Has anyone else had a similar problem?

 

[marcus_canada]

Any recurring issue like this needs to be traced back to resident parts which haven't been swapped. After all, blowing 1 Gopro is bad luck, blowing 2 is VERY unlucky, blowing 3 is downright careless.

My first thought is that you are putting voltage from the FPV transmitter into the GoPro USB port. There's only so long you can do that before something get's unhappy.

 

[DaveT1]

I disconnected the power lead. A little more history: When I connected the first H3 nothing happened. After a lengthy conversation with a GoPro tech person, he decided it was the USB port that was bad. That camera was replaced with a brand new one that would not accept the frimware updates and would not connect with the FPV. Back it went. The third one has worked for about three months before crapping out. It seems to be a problem with the USB port. That's why I was curious if anyone else was experiencing the same problems.

 

[thetac]

I do know that the wiring on the fpv board is tricky to say the least when hooking to the usb cable......red is actually the ground.....why they do that is beyond me....a multimeter is a good idea after powering up the board to check your wires going to the camera. Also I have bought a hero 3 adapter cable that was bad from the factory...i unsnapped the usb end and two wires were touching inside. I only use the two center wires off the usb wire from the camera...one is video and the other ground. If you have an fpv board that is not labeled (power, audio, ground, etc) you can't assume where the wires go. You should only need/use two wires from the fpv board to the camera...the video and the ground and they MUST be hooked to the correct two wires coming out of the camera...you should be able to unsnap/open the plastic plug in connection that goes into the camera. Unsnap and make sure that no wires are touching or grounded together.

 

[DeweyAXD]

+1 for thetac's advice.

I have noticed that the H3B is very sensitive to the correct USB cable. Cheap cables will trip it out into a frozen mode (noted by the rear red light on the Hero being faintly on). I have some USB cables that work every time when plugging the Hero into a PC and others that, when used, simply don't allow the PC to see it. Likely a voltage/resistance issue.

As mentioned here I would say it is the cable to the FPV that is likely at fault... possibly the way it is connected (if it is hooked up the wrong way it will trip the cam out). Like thetac says, given that it doesn't always trip out, it is more likely a shonky wiring job inside the 10 pin USB plug. I'd check the wiring (maybe post pics of how you have it rigged up), replace the USB FPV cable and only after that go back to GoPro.

 

[DaveT1]

Thanks for the great input. I'm going to try all of those suggestions. What I find curious, is that the setup worked fine for several weeks then suddenly quit. Secondly, after testing the cables, I found that the worked fine with a Hero 3 White. Is there that much of a difference between the White and the Black?

 

[Dskier79]

I had similar problem with my fat shark setup. Turned out to be video tx.

 

[DeweyAXD]

Thanks for the great input. I'm going to try all of those suggestions. What I find curious, is that the setup worked fine for several weeks then suddenly quit. Secondly, after testing the cables, I found that the worked fine with a Hero 3 White. Is there that much of a difference between the White and the Black?

There are a lot of differences between the Black and White. The white for example can be powered and used without a battery in it whereas the black won't turn on without the batt. This would suggest that there is something in the firmware of the black that is checking voltage input from USB and may mean it is less sensitive.

It could be the vTX - have you ever powered on without the antenna connected? If so it could be fried as the antenna is a heat sink.

Other things to note is that Timelapse mode (if you are using it) won't output a signal through USB while recording. As soon as you press record it goes black with the Hero's OSD still present. Probably not your issue but worth a mention.

At this point all you can do is change the varialbes at play to find what it is. Change the cheapest element first and work up. Much more likely a cable fault than the Hero itself IMO but the black isn't without its faults as you know. Again I would suggest posting a pic or vid of how it is wired up so we can see if there are any obvious issues.

 

[martcerv]

If powering your GoPro via in the phantom then make sure it is not giving it 12v but only 5v. I would personally never power my gopro in flight and they are very picky with voltages and how many amps they get. Safest is to make sure your FPV cable doesnt give any power to the camera and you shouldn't have any issues.

DJI power it through the zenmuse and this is one more reason I didnt get that, I have been around gopro's too long to know this will normally end badly and I dont see the point in powering a camera that lasts well over an hour from a battery used by a quad struggling to get 6 minutes with the gimbal and all.