Failsafe / receiver active question:



I would like to setup a safety relay for main power that is based on the receiver being actually linked with the transmitter. I am not looking for the normal failsafe. I would like the relay to be on any time the receiver is active and linked and off when the receiver is active but not linked. I can make half the functionality work with the basic failsafe in the sense that I can failsafe to turn the relay off when no signal or link is available. The issue is that when the receiver is linked again with a signal the relay will still turn on or off based on the PWM high or low. That means I can turn the relay off by changing the input value. What I really want is for the relay to be on with any valid signal high or low and off only when no valid signal is available do to loss of power, signal strength, out of range.



Any suggestions or ideas would be great.



Thanks for your help.

This might be tricky. If you use the regular failsafe the receiver will still send a valid PWM signal. What transmitter/receiver are you using? That might make a difference.

Assuming you can get the receiver to stop sending a PWM signal when it loses connection, you'll need some special device (eg an Arduino) to monitor that signal and trigger the relay appropriately.

I've just checked the manual for my M17 radio and it seems to have separate fail safe settings per channel. Free, set, hold. Free will stop sending a signal. Set will send a preset signal. Hold will send the last signal received. For that radio you'll want to use the Free option.

There are plenty of so called RC switches to find but yes, an intergrated failsafe can disturb your idea.

If you are a bit into electronics you could modify the receiver and use the LED link signal to switch a relay.