Is it possible to operate to operate dual Rx in one model to control selected functions

[Christopher Wolfe]

I have a model that is a test bed for a few wing options.

 

It flies nicely as designed but I wish to experiment with other wing variations (flaps, spoilers, airfoil section, aspect ratio and other variables).

 

So I am thinking, why not build the test wings with their own integrated battery, servos and receiver and leave the fuselage Rx and battery to handle the throttle, rudder and elevators.

 

This could avoid the problems of plugging and unplugging multiple leads to the Rx in the fuselage.

 

So is it possible to link two Rx to a single Tx with the output of the first Rx assigned to channels 1-4 with the output of the second Rx responding to all the remaining channels?

 

Chris

[Ron Gray]

It’s certainly possibly with FrSky equipment, I’ve done what you’ve described plus I had a steerable glider launch dolly with its own Rx controlled by the Tx controlling the glider.

[Paul De Tourtoulon]

Some radios can, My Bristol Beaufighter has everything in the wing including the twin glow drivers and battery's the fuselage has a receiver and battery for the rudder and elevator.

[Nigel R]

I have two six channel Spektrum receivers in a twin. Doesn't give twelve channels though. The six channels are duplicated across the two rxs.

 

I did it as it massively simplified the wiring. 

[Christopher Wolfe]

I should add that my test model is based on a 'Mighty Barnstormer' so quite easy to bolt a new wing on.

I am trying to avoid running a whole new set of wiring down the cabane struts.

 

Actually it's more like a 'Lego Mighty Barnstormer' as the tailplane components are bolted on so that the fin and horizontal stabiliser may be experimented with at a later date.

 

Chris

[Frank Skilbeck]

Yep, just bind both receivers to the transmitter, some brands (FrSky, Futaba, Jeti) allow you to specify/map the channels of the 2nd Rx so two say 6 channel receivers could become 12 channels. Another option if you have a S Bus compatible receiver would be to use S Bus servos in the wing (or fuselage) and then just have a single wire connection.

[Christopher Wolfe]

So it is not a matter of programming the Tx but a matter of programming the Rx so that fuselage mounted Rx only obeys input on Ch 1-4 and ignores all others

and wing mounted Rx only responds to Ch 5 and upwards.

 

This is going to be fun with my Futaba 14 SG.

 

Chris

 

 

[PatMc]

25 minutes ago, Christopher Wolfe said:

So it is not a matter of programming the Tx but a matter of programming the Rx so that fuselage mounted Rx only obeys input on Ch 1-4 and ignores all others

and wing mounted Rx only responds to Ch 5 and upwards.

 

This is going to be fun with my Futaba 14 SG.

 

Chris

 

 

You won't have to program either Tx or Rx. The fuselage Rx will ignore ch5 up because there is nothing conected to them & the wing Rx will likewise ignore ch 1-4.

[Don Fry]

3 hours ago, Nigel R said:

I have two six channel Spektrum receivers in a twin. Doesn't give twelve channels though. The six channels are duplicated across the two rxs.

 

I did it as it massively simplified the wiring. 

Knowledge quest, how did you do it?

[Christopher Wolfe]

5 hours ago, PatMc said:

You won't have to program either Tx or Rx. The fuselage Rx will ignore ch5 up because there is nothing conected to them & the wing Rx will likewise ignore ch 1-4.

Thanks PatMc.

 

So blindingly obvious now that I think about it.

 

Chris

[Frank Skilbeck]

Chris, not sure which Futaba receivers you are using, but you can configure say the 7008 ones so that they either receiver channels 1 to 7 or 8 to 16 (obviously 14 with a 14 SG), or just use the S Bus output and the new Futaba SU300B  S-bus servos in the wing, so you'd have a single wire connection from an S-Bus hub to the rx S Bus port, the fuselage servos can plug into the regular servo sockets. You can configure each servo to respond to a specific channel.

[Nigel R]

8 hours ago, Don Fry said:

Knowledge quest, how did you do it?

 

As easy as - bind the rx one at a time. Power only to the rx being bound. Job done.

 

To add some detail to the data point I used 2x ar610 and a 2nd gen DX8.

 

I half remember seeing it in the manual? But that might be a delusion induced by Christmas over indulgence...

[PatMc]

1 hour ago, Nigel R said:

 

As easy as - bind the rx one at a time. Power only to the rx being bound. Job done.

 

To add some detail to the data point I used 2x ar610 and a 2nd gen DX8.

 

I half remember seeing it in the manual? But that might be a delusion induced by Christmas over indulgence...

I think you can do that with just about any brand using Rx's on the same protocol.

Phil Green, of this parish, was the first person I'd read of using this system. He posted some years ago that when required he could temporarily convert a glider to take a electric power pod using a small second Rx plus ESC in the pod for motor control.

[Graham Bowers]

10 hours ago, PatMc said:

I think you can do that with just about any brand using Rx's on the same protocol.

Phil Green, of this parish, was the first person I'd read of using this system. He posted some years ago that when required he could temporarily convert a glider to take a electric power pod using a small second Rx plus ESC in the pod for motor control.

Now that, I like 😉

[Frank Skilbeck]

Dual receivers are part of the requirements for meeting the redundancy requirements for over 25kg models, either as part of a linked system or with split controls. One issue to watch is if they are telemetry receivers to make sure they don't send conflicting information back to the transmitter.