I finally decided to give a go to FPV flying with my quadcopter using an FPV camemera as when I tried flying through the GoPro mounted on a 3 Axis Gimbal it was almost impossible due to the smoothing out that the gimbal is introducing as well as keeping a level horizon.
Of course I was already aware that the general consensus is to never use a GoPro for FPV but for keeping things simple I started with what I had at the time.
So I went ahead 2 weeks ago and ordered the parts I required on top of my existing setup:
- An FPV Camera 700 TVL 1/4” CMOS Wide Angle
- A 3 Channel video switch
- The FrSky FLVSS Voltage Telemetry module for smart port
The components that I already had on the quad-copter are:
- APM minimosd
- 5.8 Ghz Video Transmitter
- FY-G3 Ultra 3-Axis Brushless Gimbal
- 3DR Radio Set for Pixhawk Telemetry data exchange
- Black Pearl FPV Monitor for my ground station
As I wanted to be able to use a single VTX but have the ability to watch both camera feeds I looked it up and found that the best way to do that would be by using an FPV video switch.
There are a few brands available but I chose the G.T.Power FPV 3 Channels Video Switcher as it was good value for money and had plenty of great reviews.
This switch would allow me to select which camera I would like to see through my Ground Station monitor, by remote controlling it with my Transmitter. The switch also automatically switches the camera if the signal from the active channel is lost; for example in case of hardware failure.
Even though I have the 3DR telemetry on board the through the minimosd will superimpose the voltage readings and in adition to my mobile phone that would announce battery percentage I wanted to have another source of voltage readings and more specifically I wanted to know the voltage of my lowest cell.
The FrSky FLVSS was the answer to my requirement as by plugging it onto the RX (X8R) I can programme my Taranis to read the voltages out load as well as display them.
Wiring an FPV camera and the rest of the components
Honestly the trickiest part with all these electronics in my hands is getting the wiring right and unfortunately there aren’t many if any sources on the web that would have the same setup as I do, so I tried to be as careful as I could and took my chances when I finally connected the main power source.
Below I have a diagram with my current working wiring. As I mentioned in my previous blog post regarding the pixhawk wiring, I am not 100% certain this is correct, however it has worked and so far I haven’t damaged any components!
The video quality is great and there is no interference or sign that something is wrong.
- The minimosd board is bridged and powered only from the Pixhawk
- The FPV camera takes its power from the VTX +Vout which on the specific VTX supplies 0.5V less than the input voltage. And as the FPV camera accepts 8-13V it was safe to power it this way
- The FPV Video Switch is powered by the RX which in turn is powered by the pixhawk. This circuit is separate from the Camera circuit so the voltage difference isn’t a problem.
- In this diagram I don’t show the connection of FLVSS with the RX as this is pretty straight forward and through the smart port.
I hope that these screenshot from the OpenTX companion will be useful for someone. If you have require any further explanation, do not hesitate to drop me a message or comment below.
I haven’t yet flown in FPV to comment on the experience as it’s still really chilly (3C-5C) outside to venture in the open fields. However I will be updating this post as and when I have further news.