FPV newb: Can I power the VTX from the Rx?

[jtrops]

I want to install an eachine Tx02 all in one camera/vtx into an Arrow. Can I power this from an auxiliary channel on the Rx? My thought is that the voltage should be fine, and it would give me the ability to turn the camera on from the Tx via a switch. Since I'm completely new to FPV I'm sure there are things I'm not considering, and this is where I could use some help.

Thanks,

Jerry

 

[ElectriSean]

You could probably get away with powering from the Rx as the current usage is fairly low, but to switch it on or off requires a receiver controlled switch - something like https://hobbyking.com/en_us/turnigy-receiver-controlled-switch-1.html?___store=en_us as the signal pins are not designed to carry much current at all, just a signal.

 

[Montiey]

You'd need a module to operate the camera from a switch (and I must ask, why?). You weren't thinking of hooking the power lines up to GND and Signal, were you?:black_eyed: That's not going to work, because the signal lines only output ppm, so you can't actually control the voltage by changing the signal. Plus, they are not meant to have any actual current drawn- the electronics in the servo / esc they are connected to only sense the voltage, without any real current draw.

You can, however, connect it directly to the RXs + / - rails just fine. It will receive power from the UBEC or BEC as if it's a servo. The datasheet says it can accept 3.3-5v, so you should be fine.

Edit: I was too late

 

[jtrops]

Thank you for both replies. I guess I didn't think about the switching signal, but that doesn't really matter. It should be easy enough to put a connector on to hook it up to the power rails on the Rx.

I did a test with it hooked up to a 1s battery and it worked better than I expected. This is just to keep more stuff out of the fuse on the Arrow since it's a pretty close fit for everything already.

 

[TazRC]

FPV Camera Power Options

You can use a servo Y-connector on the ESC receiver lead and just splice the FPV camera connector on one end. If you have problems with noise in the video transmission, you can use a small LC filter at the splice. Or you can use a filter/regulator from the battery balance tap to the camera.

 

[PsyBorg]

You really should not be powering anything with the receiver other then maybe the FC. The more current you draw thru that rail the higher the chance for brown outs and crashing your system. Besides the receiver does not have any power filters and will more then likely allow for a lot of video interference and giving poor video results.

 

[jtrops]

You really should not be powering anything with the receiver other then maybe the FC. The more current you draw thru that rail the higher the chance for brown outs and crashing your system. Besides the receiver does not have any power filters and will more then likely allow for a lot of video interference and giving poor video results.

This is good to know. I had a feeling there was probably some reason not to do it. Since the bec is in the esc it makes sense using a y connector from the esc.

 

[TazRC]

If you don’t get too much noise, it will be fine on a flying wing with only 2 servos. I’ve done it before. Just make sure the BEC Amp rating of the ESC is enough for the estimated combined Amp draw of servos, RX and camera.

Lemon Rx produces an FPV camera that runs from a receiver. You can change channels and turn it off and on from the radio. Lemon Rx sent me one to try out but unfortunately it lacks camera quality so I don’t recommend it. http://www.lemon-rx.com/index.php?route=product/category&path=80