Good day.
I usually fly helicopters but I bout a quadcopter, pixhawk, 3dr radios and gps.
I realise the pixhawk uses PPM. I have a 7ch spektrum receiver. I was wondering, for a quadcopter, do I need 8 channels or is 7 channels enough? Because I know that aruducopter for helis needs 8 channels. So can a 7 channel receiver work for quads?
Next question.
Is is better to use a normal receiver and ppm encoder or a ppm receiver? Bear in mind I already use a spektrum DX8 radio and spektrum has no ppm receivers. Only a company called lemon rx and I dont know if I can trust them.
Replies
Can 2 or more spektrum remote receivers be connected to the Pixhawk for a standard diversity solution?
With just a satellite you do not get the protection of the throttle failsafe. Satellites do not have failsafe capability.
We have used the LemonRC with PPM and failsafe on the Pixhawk with good success. Hopefully Spectrum may release a similar product with more and more flight controllers requiring PPMSUM inputs.
Nope, the satellite is a receiver, just without the servo pins and such.
Two satellites would be the most robust so you can have some diversity.
As Chris said, just get a Spektrum satellite and plug it into your Pixhawk, then you will have all 8 channels in a clean setup.
You really only need 5 channels to fly: 4 for the controls and 1 for mode selection. I use 6 with the extra one to control tilt of my camera gimbal.
Seven channels is fine for a quadcopter. Although Pixhawk is designed for PPM receivers, it has a special port for the Spektrum satellite connection, so you should be able to use the radio gear you already have.