Reciver interface

[ManTin361]

Hello again!

I'm trying to set up a system that allows me to either control my plane by remote or by the autopilot I'm building. In order to do this, I am planning on sending the PWM from the receiver into a "Controller Switch" which then decides what will control the airplane (the autopilot or the receiver). To do this I need to convert the PWM to a clean analog voltage which will then go into an A to D on a PIC. My problem is I can't filter out PWM correctly. I've tried both passive and active low-pass filters but I get too much noise.

I wanted to know if anyone has tried to filter out the 50Hz PWM from a RC receiver or if anyone has any ideas on how to do this.

Thanks for any advise,
Matt

[kd7ost]

Sounds like you've chosen a difficult path Matt. Unless you're using something other than standard servo's at the control end that is. Here's an extensive thread completely outlining how to switch the signals between your RC receiver and your autopilot system. But it leaves the pulses intact. I think you will find that using a mux chip controlled by the PIC chip is a lot simpler and more reliable than using all the components needed to change your digital pulses to an analog signal, then convert them back to pulses again.

http://www.rcgroups.com/forums/showthread.php?t=360746

Dan

[ManTin361]

Thanks Dan! That is an obvious solution that I never thought of.

Thanks!!
Matt