Pixhawk, OSD and TELEM problem

ArduCopter Traditional Helicopter
1

Hello,
I’ve built a 450 size helicopter.
I have an FPV camera with telemetry OSD on it. The cam is on a second 3s 650mAh battery.
OSD is OK on screen but as soon as I start engine, OSD disappear.
I’ve test OSD on TELEM1 and TELEM2, the same.
Why does the OSD cut off?

see the vidéo:

2

Make sure you use the common ground between the CAM,OSD board and Transmitter. What board are you using?

3

Hi.
It’s a pixhawk 2.4.8 FC.

4

Hi, you might have left the OSD toggle switch on ch8.

5

You’re right!!!
it was the MinimOSD config display switch. It was set to CH8.
Thank you!!!