Thoughts on FrSky Redundancy buses

[Jeronimo770]

I am planning a step up into turbine jet aircraft and I do want reliability from my radio system. I'm thinking a redundancy bus installation is the right approach but I have read various threads discussing problems.
I have an X18 Tx running Ethos 1.6.0 currently but may update to 1.6.3 Do I need 1.7.0?

On the redundancy bus matter, I'm likely to go for the RB-40. Any problems reported from these, please? I doubt having need for more than 16 channels.

Advice appreciated, thank you. Jerry.

 

[Wayne]

For sure you want to be on current firmware. Always a best practice.

The German forum is probably going to be the best place to read up on any possible issues with the RB units:

Dashboard - FrSky-Forum

www.frsky-forum.de

They tend to fly a lot of the big stuff and they love a deep dive into the electronics. Engel and their crew do a great job staying on top of any issues and pushing for FrSky to fix any bugs that pop up. It might be a little work, but probably your best discussion area.

 

[HENNY]

I am planning a step up into turbine jet aircraft and I do want reliability from my radio system. I'm thinking a redundancy bus installation is the right approach but I have read various threads discussing problems.
I have an X18 Tx running Ethos 1.6.0 currently but may update to 1.6.3 Do I need 1.7.0?

On the redundancy bus matter, I'm likely to go for the RB-40. Any problems reported from these, please? I doubt having need for more than 16 channels.

Advice appreciated, thank you. Jerry.

1.6.3 is the current radio firmware, 1.6.4 is under development. 1.7.0 referres to Ethos Suite firmware, the firmware that runs on a laptop. I would recomend Tandem receivers as these run both 2.5g and 900meg transmissions at the same time giving you a lot of RF security. RB30 and 40 are a dual receiver inputs with their own redundant power supplier. So you will also require two receivers to drive the whole system. Also best to check the receiver firmware versions as this has been developing with time. You should also check the receivers and transmitter have the latest version-3 RF firmware.

 

[Jeronimo770]

Again, slow response, sorry.

Just to complete this thread, I have chosen to use the TD SR18 receiver with a TDMX as the redundancy receiver. A much more straight forward setup which fulfils my need for dual power and Rx safety. All updated to latest firmware.

Thanks for your advices. Cheers, Jerry

 

[bubbasks]

I am planning a step up into turbine jet aircraft and I do want reliability from my radio system. I'm thinking a redundancy bus installation is the right approach but I have read various threads discussing problems.
I have an X18 Tx running Ethos 1.6.0 currently but may update to 1.6.3 Do I need 1.7.0?

On the redundancy bus matter, I'm likely to go for the RB-40. Any problems reported from these, please? I doubt having need for more than 16 channels.

Advice appreciated, thank you. Jerry.

I haven't messed with the RB units yet but I have 7 jets set up and all use a tdr18 with tdr10 back up(I use these just so if something happens I have a spare pwm receiver) the TDR 18 handles plenty of amperage even for my 41% carf extra 330 doing mild 3d. Jets range from 1.7m to 3.5m ltma-1 planes. And no need for the 1.7 updated, hell I flew on 1.4 up till 6 months ago. 1.6 has been very stable for me.

 

[Jeronimo770]

Thanks for that bubbasks.

Further update on this. It has become clear to me that the 900MHz transmissions from the TD receivers cause serious problems for the electronics in models. In particular, I was going to install a KingTech turbine in this plane. KingTech's response to a query was DO NOT USE 900MHz. This is because the 900MHz causes serious interference with the turbine control possibly/likely resulting in flameouts - particularly at idle speed. Additionally it is reported that the 900MHz can cause significant jittering in the servos. All too much for me and I am changing to use the FrSky Twin system of dual 2.4GHz. With the TW SR12 and TWMX receivers I get the wanted redundancy and stabilisation and I can fit the FrSky Twin Lite Pro external module to my X18 Tx. Solves all the problems . . . . I hope

 

[Wayne]

Has anyone reported any issues with servo jitter from 900? We have not heard a peep here, and trust me we would hear from our customers.

Now I would suggest avoiding the KingTech if they admit to knowing they have a 900mhz issue and are continuing to sell. 900 is all around us and at all sorts of power and concentrated beams. It is used in so many applications these days. Yikes!

Any manufacturer in the aviation field should not be selling anything that is known to have an RF intrusion weakness.

Now in the old days people used to blast really dirty stuff with cheap video transmitters. That is hard to combat as those things were super dirty and super powerful. Luckily those things are all in the trash heap these days. Perhaps that is what KingTech was referencing? I have no idea. But all MAJOR radios for turbines these days use 900. Jeti, Core, FrSky, etc. (I don't consider Spektrum to be a turbine radio!)

 

[Red]

Has anyone reported any issues with servo jitter from 900? We have not heard a peep here, and trust me we would hear from our customers.

Now I would suggest avoiding the KingTech if they admit to knowing they have a 900mhz issue and are continuing to sell. 900 is all around us and at all sorts of power and concentrated beams. It is used in so many applications these days. Yikes!

Any manufacturer in the aviation field should not be selling anything that is known to have an RF intrusion weakness.

Now in the old days people used to blast really dirty stuff with cheap video transmitters. That is hard to combat as those things were super dirty and super powerful. Luckily those things are all in the trash heap these days. Perhaps that is what KingTech was referencing? I have no idea. But all MAJOR radios for turbines these days use 900. Jeti, Core, FrSky, etc. (I don't consider Spektrum to be a turbine radio!)

I've been using 900MHz for 25+ years as the standard in the UAV world without issue. I would think that there must be more to the story.

 

[Wayne]

Konrad sent me a message and confirms that King Tech EGT leads do not like 900 when the transmitter is nearby, but says the solution is to reduce the 900 output on the radio. He does suggest that 2.4 needs to be backed up with something other than more 2.4 at his turbin fields he frequents. He reports that all of the reported radio issues at the 2025 Jets over the Rockies jet rally were using Spektrum 2.4. (As stated I do not consider those radios a viable option for turbines or any larger aircraft.)

I suspect that the TWIN system will be fine, using LORA transmission really makes that a much more robust option than our normal 2.4 systems. With this said - ALWAYS do your own testing with these larger and more complex aircraft! You need to confirm your RF is stable and reliable prior to flying.

 

[bubbasks]

Thanks for that bubbasks.

Further update on this. It has become clear to me that the 900MHz transmissions from the TD receivers cause serious problems for the electronics in models. In particular, I was going to install a KingTech turbine in this plane. KingTech's response to a query was DO NOT USE 900MHz. This is because the 900MHz causes serious interference with the turbine control possibly/likely resulting in flameouts - particularly at idle speed. Additionally it is reported that the 900MHz can cause significant jittering in the servos. All too much for me and I am changing to use the FrSky Twin system of dual 2.4GHz. With the TW SR12 and TWMX receivers I get the wanted redundancy and stabilisation and I can fit the FrSky Twin Lite Pro external module to my X18 Tx. Solves all the problems . . . . I hope

Twin works very well. I haven't had any issues with KT and 900. How close is your antenna to the ecu or turbine? Certain servos hate 900 but most issues can be solved by turning 900 down to 25mw in the receiver menu

 

[bubbasks]

Has anyone reported any issues with servo jitter from 900? We have not heard a peep here, and trust me we would hear from our customers.

Now I would suggest avoiding the KingTech if they admit to knowing they have a 900mhz issue and are continuing to sell. 900 is all around us and at all sorts of power and concentrated beams. It is used in so many applications these days. Yikes!

Any manufacturer in the aviation field should not be selling anything that is known to have an RF intrusion weakness.

Now in the old days people used to blast really dirty stuff with cheap video transmitters. That is hard to combat as those things were super dirty and super powerful. Luckily those things are all in the trash heap these days. Perhaps that is what KingTech was referencing? I have no idea. But all MAJOR radios for turbines these days use 900. Jeti, Core, FrSky, etc. (I don't consid sureer Spektrum to be a turbine radio!)

Hitec servos like the 625/645, 5625/5645 hate 900 as well as MKS 777 from my knowledge have been known to hate 900 even with turning down. The issue with KT I have yet to experience in 4 builds I've done involving FrSky and one of their turbines. Possibly bc I keep radio equipment and turbine equipment as far away from each other ass I can. Most manufacturers recommend 12 inch to be on the safe side if possible.