Runcam Swift 2 audio noise

I am facing some audio noise with Swift 2. I have connected audio straight to transmitter, ground is connected to flight controller ground pin. Here is a video of that noise >>

Hey febeks,

try connecting GND to exactly same device like 5-36V wire. Since chances are, that the VTX has it’s own Vregulator, you pretty sure will run into interferences any other way.

Well it is connected to flight controller, both GND and 5V.

Sorry i missed that.

might try this:

  • try connecting power for the cam to the VTX
  • (if not already) make VTX antenna point away from camera
    Hope this helps

Im not sure but I dont think I have a pad for power on VTX. Well there is a +12V and GND pad but can I use it?
Take a look

And VTX antenna is pointing away from camera, I would say it is in 90 degree angle.

I see.

Don’t know now what the 12V pad is for, but it seems that the connector has a 5V supply, there is a regulator circuit below ‘170221’.

Tell me brand and type, so i can check it.

It is TX35B. Don’t have more information about it. That connector has 5V supply but wires that go to that connector are those from flight controller.


It’s labelled 5V OUT, not IN.

If you have connected it to a 5V OUT on the flight controller, both would be ‘working againast each other’.
Open this 5V-connection and check the results. You might get less noise with this step.
Make sure, you have any wires insulated while trying!

So should I connect camera GND and 5V to the VTX?

Most likely, yes.

You have sort of ‘horizontal lines’ in the video, too. I expect sound to be fixed and video a little smoother.

Okay, I will do that next week cause I dont have solder iron with me right now. I will post an update then and will let you know. Actually, maybe I will borrow from a friend so I might try it even today, will see :slight_smile:

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Okay, I did that but no change at all.

:open_mouth::open_mouth::open_mouth: WHAT?
ok, so you have audio + video + 5V-36V + GND wired from cam to VTX. There is no connection of the 5V wires/pads between FC and VTX?

Do you have any chance to check the cam on another vtx?

There is 5V and GND connection to FC. That VTX is brand new should be working fine.
I got fixed video interference (lines) using a foam like in this video but audio is still noisy.

So if there’s a 5V connection between VTX and FC, what connetion do you use to power the VTX?

from FC wire goes to VTX to 5Vin on that connector that u posted picture above. that is how VTX gets power.

But the label on the VTX doesn’t say 5V, it says DC7-24V. If you have it powered from 5V, this is wired incorrect.

Okay I double checked and power into VTX comes from B+ pad on FC, here is a picture where you can see B…I checked documentation and it says B+.

Its the bottom picture, 3pin connector with yellow, black and red wires. Its old picture, yellow wire is not there anymore since it goes straight to VTX. Only red and black go from FC to VTX.

That vtx is designed for 2s minimum, in other words connect straight to main Lipo leads. Give it the correct voltage and it should work fine.

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I advise against connecting a Lipo to what you have currently wired up. High risk of damage to both fc and vtx. Possibly even a fire risk.