Rx4R redundancy plus dual rx

Welcome to our Community
Wanting to join the rest of our members? Feel free to sign up today.
Register

Robin

New member
Sep 21, 2018
7
0
#1
Was wondering if it’s possible to use two rx4r connecting both sbus in and out on each.
1 To have redundancy
2 To have Pwm ch 1 to 4 on one and 9 to 12 on second.
This would be in a 4 servo wing glider one rx in the fuse second in the wing centre section, just the one neat connection
Each could be the back up for the other for signal

Any ideas on this one please 😊 cheers
 
May 31, 2018
42
4
#2
The RX4R supports PWM channel shifting from 1-4 to 9-12 (see manual) so part of what you suggest is possible.

However the R-Bus is intended to be master slave so it is undefined what will happen if you connect them symmetrically as you propose.

The way RBus works is that the master RX will use its signal unless it gets a bad packet and then it will look at the slave SBUS to see if there is a good packet and if so it will use that. Presumably it will send out the combined "good" SBUS packets or a packet loss if neither are good.

You do have to switch off telemetry on the "slave" RX with an R-bus setup but there is nothing else that says it is the "slave" so presumably it does the same thing with the SBUS in it receives.

Once minor concern is that they will be some delays in this that could affect failsafe but I'd have to think that through.

So I'd say it might well work but you would have to test it thoroughly. Easy enough to bench test. You can simulate the switch over using different RX numbers when you bind to switch between the two RXs. Make sure to bind them with the same RX number after the test. Not exactly the same as an in flight failover but its logically similar. Shielding the antennas is a more accurate simulation but its less easy to be sure what is going on.
 
Last edited:

Robin

New member
Sep 21, 2018
7
0
#3
The RX4R supports PWM channel shifting from 1-4 to 9-12 (see manual) so part of what you suggest is possible.

However the R-Bus is intended to be master slave so it is undefined what will happen if you connect them symmetrically as you propose.

The way RBus works is that the master RX will use its signal unless it gets a bad packet and then it will look at the slave SBUS to see if there is a good packet and if so it will use that. Presumably it will send out the combined "good" SBUS packets or a packet loss if neither are good.

You do have to switch off telemetry on the "slave" RX with an R-bus setup but there is nothing else that says it is the "slave" so presumably it does the same thing with the SBUS in it receives.

Once minor concern is that they will be some delays in this that could affect failsafe but I'd have to think that through.

So I'd say it might well work but you would have to test it thoroughly. Easy enough to bench test. You can simulate the switch over using different RX numbers when you bind to switch between the two RXs. Make sure to bind them with the same RX number after the test. Not exactly the same as an in flight failover but its logically similar. Shielding the antennas is a more accurate simulation but its less easy to be sure what is going on.
 
Jan 23, 2018
76
4
60
Sydney, Australia
#5
Can anyone advise, the factory firmware, has it been updated yet? there is a download on the Frsky web site labelled first release, is it the same as the factory firmware? I don't have issues, just want to keep up with improvements if any.