Can't connect Futaba receiver to Pixhawk Mini

I recently purchased the Pixhawk Mini. I am unable to connect the receiver.I am using Futaba receivers - R6208SB and R7008SB. When I connect R6208SB to Pixhawk mini, the led glows red for a second and turns off. When I connect R7008SB, the led glows solid red but it doesn’t pair with the transmitter. I tried connecting with USB and battery, still nothing works. But when I connect both the receivers to the normal Pixhawk, they work fine. What is the problem?

Hello,
you can try to power the rx separate. I had a problem with a frsky receiver witch draw 100mA. Jeti RX 50mA worked powered by PH-Mini. I guess there is something with the voltage regulator different to other PH. I fried also a Pixfalcon when I connected minimOSD and bluetooth, both where powered separately, but probably there was a ground loop or something. At the moment Mini is running fine with only gps powered from it.

Hello

You have used a 50mA receiver. So how much current does the RCIN port in Pixhawk Mini supply? Depending on that I can opt for another receiver.

Option 2, to power up the receiver separately. I am using a Mateksys PDB with a 5v and a 12v supply. Not using the stock PDB because I want 12v for camera. I am powering up my Pixhawk from the 5v. Can I use the same 5V to give power to the receiver? will that be a problem?

I use the same 5,3V source for RX and Pixhawk. With a second 5v regulator I fed the USB. I can’t find and don’t know any tech specs about the power regulator.