Using Dual RX's Anything I need to know?

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stukno
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Using Dual RX's Anything I need to know?

Post by stukno » Wed Mar 26, 2014 10:35 pm

Hi All,
I'm a new member here with a very non technical question:-
I want to use two D8R II plus receivers in one model to give some redundancy should one fail. Obviously both are sending back telemetry to the TX. In the workshop it seems that the Telem screen flickers between RX 1 & RX2 but otherwise it all seems OK.

Is there any negative to using this setup? any harm or tech reason why two such RXs should not be used side by side?
Any way that each RX battery and RSSI could be monitored separately. I'm not intending to use any other telem sensors

Many thanks

stu K
UK

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MikeB
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Re: Using Dual RX's Anything I need to know?

Post by MikeB » Wed Mar 26, 2014 10:52 pm

What firmware are you using?
I cannot think of any way you could monitor the telemetry separately from the two receivers if they are both operating from the one Tx module.
You might be able to do something if you use a XJT Tx module and two X8R receivers.

Mike.
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stukno
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Re: Using Dual RX's Anything I need to know?

Post by stukno » Thu Mar 27, 2014 8:16 am

Hello Mike, Thanks for commenting. Everything being used is 'as supplied' how do I know what the firmware version is?
If there is a way to use dual RX's and retain RX battery voltage monitoring then I'd be grateful if you could point me in the right direction, even if that means swopping the present RX for a different model. Although the model is not over 20KG weight where dual RX / flight control redundancy is a requirement, it's getting up there and it's one that I would hate to loose. It has dual batteries, each battery able to power both RX's, dual switches, dual power leads to each RX and then flight controls split over each RX so that if one fails some control is retained.

Thinking about it, it might be better if only one RX was sending telem data? although I can't see that two actively sending can do any harm, just confuses the display a bit.

If anyone has any useful thoughts on how best to do this I'd be pleased to hear them.
thanks all

stu k

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MikeB
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Re: Using Dual RX's Anything I need to know?

Post by MikeB » Thu Mar 27, 2014 2:11 pm

What are you using to display the telemetry?
What is the RF module in the transmitter?
What transmitter are you using?

With both receivers sending telemetry, you are always going to get a confusing/flickering display.

Mike.
ersky9x/er9x developer
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jhsa
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Re: Using Dual RX's Anything I need to know?

Post by jhsa » Thu Mar 27, 2014 2:21 pm

He could use a frsky V8-II receiver.. It will bind in D mode. The he will have a D series receiver sending telemetry and the V8 (non telemetry) for redundancy, both bound to the frsky TX module. I think that might work?

João
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stukno
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Re: Using Dual RX's Anything I need to know?

Post by stukno » Thu Mar 27, 2014 7:31 pm

Hi Thanks again for the comments.
I am using a Multiplex Royal Ev0 12 with internal hack module and external lcd screen unit. I had some help to fit the hack unit and to minimise the space required we removed the switch needed to operate early V series receivers. At the time I had no Fr Sky gear so only buying telem RX's seemed a sensible option. How these things come back to bite you on the AXXXX!

I've been rigging this model today and making final adjustments. If I have to sacrifice reliable telemetry in order to gain on the redundancy benefits arising from two Receivers, it looks as though thats how it will have to be. I just thought that there might be a way of switching one off or something similar.

stu k

stukno
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Re: Using Dual RX's Anything I need to know?

Post by stukno » Thu Mar 27, 2014 7:34 pm

Hi again,
Joao, I've just read your post properly. I thought that 'V' receivers would not bind in D mode?? Can anyone confirm as using one telemetry RX and one non-telemetry RX would seem to at least give one clear telemetry reading?

thanks to all
stu k

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jhsa
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Re: Using Dual RX's Anything I need to know?

Post by jhsa » Thu Mar 27, 2014 9:04 pm

The "V receiver Version 2" can bind in D mode. The very old "V" version 1 doesn't. I think it should work, and you should have the telemetry from the D series receiver. But I can't test it for you as I don't have any V receiver :(
Maybe someone has and can test it please?

João
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