Unable to bind SRXL2 Sat SPM9747 with Spirit GT and 4651T

[Mattes61]

Hello Tomas,

Since I am also interested in that, I have a few questions - Yes, you are right, Spektrum has always said to use at least one receiver and one satellite or more and I am already talking about the normal DSMX2 satellites without telemetry - despite all of that all flybarless manufacturers offer a Sat1 and Sat2 port, although this is actually not recommended (spektrum) - then the question arises for me, why do you allow such interfaces if they are unsafe?

The question that arises with the current SRXL2 satellites is whether the whole thing works reliably and whether a second satellite can possibly compensate for shadowing of the other satellite - this is already relevant with a larger helicopter. I have not found anything about the SPM9747 that it is not permitted in a helicopter - furthermore only the telemetry has no full range (fly by) but the satellite does! The "problem" that the SPM9747 also transmits telemetry cannot be, because even the spektrum's own FBL (FC6250HX) offers the option of using another satellite, such as the SPM9747, in addition to the 4651T - this also applies to the SPMAR6610T, which itself also has full range for telemetry, can also be connected to an SPM9747 - This means that there shouldn't be any negative interference between the two receivers - the question is, can the Spirit FBL handle this without any problems and only you as the manufacturer can answer that, we as end users have no insight into it -

Sorry that I've written so much now, but as I said, the topic interests me too, that's why it's so important
to me - the other spektrum users are interested in in any case at least as much as me - a final clarification would be necessary and helpful -
Thank you in advance for answering from you and your team!

Many greetings
Matthias

Last edited 10.12.21 JPG for AR6610T...

[ZeXx86]

As you can see at the photos, there are not two SRXL2 sats, but two old Spektrum satellites.

Why we offer two sats? Because people want it. But still we recommend full size receiver.

I can't tell you how it is reliable, this must be answered by Spektrum. We can't do more to offer the highest reliability. FC main task is to only power it and then read data. And there is nothing else we can do about reading the data.

So our recommendation is and always was to get full size receiver and satellite if you want maximum reliability, regardless of it is is old satellite or new satellite.

[Mattes61]

Hello Tomas,
what photos do you mean ? In the Manual ?
Of course, the risk lies with the end user if he only flies with satellites, this is warned by all FBL manufacturers, I understand that too - Why I want to re-inquire is because beserkr told about his problem here in the forum and I said in this one thing I am also interested. My question is, how can a user check whether both satellites are working or if one fails, that the other is successfully forwarding the signal and thus maintaining the connection - is there a way to be able to determine this via Spirit Telemetry and possibly log too (GT)? Is there anything planned here?
Tanks im advance !

Many greetings
Matthias

[Mattes61]

Hello Tomas,
now I understand your first comment that the photo shows only old sat ports - I have read an article in helifreak you can take two old DSMX2 receivers that's right (RX1/RX2) but you can also take one additionally SRXL2 receiver at the RX1 port, you only have to make an adaptor cable 4 to 3 cable, see in the hardcopy of helifreak from brianbremer horizonhobby!

Best Regards
Matthias

Last edited 12.12.21, 15.28 O'clock comment corrected -

[beserkr]

It seems that it is working without any issue for us.
However I have to point out that Spektrum do not recommend running 2 SRXL2 sats because both are transmitting telemetry.
Also SPM9747 is not designed for helicopters. Range is lower than for 4651T.

Preferably full size receiver and sat are always the best solution and recommended by Spektrum.

Can you please explain how you tested this? Did you use exactly the same configuration?

Spektrum 4651T connected to ELE/PIT/AIL and RUD
Spektrum 9747 connected to SAT2
Initialise model, confirm both receivers are lit up and bound
Remove the cable from the 4651T

And your setup did not go in to fail safe? With only the 9747 connected to SAT2 (but the model initialised with the 4651T connected also)?

The 9747 is simply an updated version of the older 9645 and 9745 satellite receivers which many people use on helicopters with great success. To compare, at the same flying field a friend of mine has a Spectrum FC6250HX FBL, running with only a 4651T and a SPM9745 satellite and has zero issues whatsoever.

This hints to me that support is missing in the Spirit FBL for this type of configuration.

As has already been mentioned, the 4651T provides full range control AND telemetry, whilst the 9747 provides full range control and (I think) fly-by telemetry. I know several helicopter pilots who are using 4651Ts and the 9747 or 9745 satellites with other FBLs without issue. In fact, I recently built a Logo 800 using a Brain 2, 1 x 4651T and 2 x 9745 satellites. It works perfectly with almost zero signal loss, and unplugging any two of the three receivers still leaves the pilot in control of the model.

The guy I built the 800 flies Spektrum and has many models (Logo 800, Trex 700, Logo 550, soon to acquire a TDR2 and more) and wants me to fit Spirit GTs in all of his models after I demonstrated how well the Spirit GT performs in flight. However, I can't recommend the Spirit to him until we get a satisfactory answer regarding the issues I've experienced with my, very similar setup.

I understand that you prefer us to use a "full" receiver such as the AR10100T, but that option (A) adds weight and wiring complexity and (B) is 50% extra in cost compared to using the 4651T and 9747 combination. If it works with other FBLs (Spektrum, Brain/Ikon), why not with Spirit?

To reiterate, I love the features of the Spirit GT and the way it flies and I sincerely hope I've just made an error in my setup, but the way my question has been answered doesn't fill me with confidence. I may have to sell my Spirit and get another FBL, since I can't afford to replace my radio system and can't fly my 550 waiting for it to fail-safe and crash at any moment...

[ZeXx86]

Hello,

we have used exactly same setup and also tested all possible variants of SPM4650, 4651 and 9747. All were working always exactly and there was no issue.

If you think your 9747 sat does not work with Spirit, then you can try other 4651T sat from your next model.
In this way you can confirm compatibility.

I can`t know if completely all versions of available satellites are compatible, since there is chance they are not identical. For example with old 4649T there were different hardware variants even that it was named in the same way.

So in other words, it is working with all Spirit units with no issue in our tests. We added support for multiple SRXL2 sats sooner than Brain actually.
I can even take a video for you if needed.

Recently we bought also Spektrum NX radio because other customer thought integration is not working with Spirit there.
Fortunately all is working there in fact. The only issue was different control of radio from older Spektrum models - roller behavior is different.

[beserkr]

I wonder what is different, from your setup to mine then?

As indicated by your testing, I must be doing something wrong, or one of my components if faulty.

-Spirit GT is on latest firmware, 3.3.3
-4651T and 9747 are on latest firmware. Both receivers were bought brand-new for this model
-4651T is connected via modified Jeti integration cable to RUD and ELE/AIL/PIT port
-9747 is connected to SAT2 port with correct adapter cable

I power up the model and wait until the Spirit has initialised. Both receivers are lit up , showing they're correctly bound to my DX9. In this state, I can control the model. If I now unplug the cable from the 4651T, I lose control and the model goes to failsafe.

If you can do this, and continue to have control after unplugging the 4651T then something must be wrong with my configuration.

I'd honestly be very happy for you tell me that I'm doing something wrong and show me how to correct it. Is there more information I can provide which would help Tomas?
I don't have any more receivers to test with, but will see if I can borrow some from friends to test further.

I'm happy to make a video of what happens with my setup, if that helps?

[ZeXx86]

Hello,

you can try to connect just one sat to AIL pin. Then connect the same receiver to other SAT port after initialization.
And it should work regardless of what SRXL2 type it is.

[Mattes61]

Hello beserkr,
may be you can try to connect the SPM9747 instead of 4651T at the ail-pin and the 4651T at the sat port this should also work because both satellites have an minimum voltage of 3,3V - works that, if yes then you can try to disconnect the 4651T and see if the 9747 can take over - Or you can test respectively the 4651T or the 9747 alone if they work alone for it (at the ail pin) - If they will work alone then the satellites are both ok !

Maybe there is then an communication problem in the FBL and nobody knows about it before ?

@Tomas
Please do me not misunderstand, that's not against you and your company !
I am a happy pilot with Spirit Systems !!
But when both satellites are working correctly for themselves there can be no other possibility in my opinion when they should work "together" -

If I am wrong, then I am sorry, but I have no other explanation at this moment-

Best regards
Matthias

[beserkr]

OK! So I just tried what you have both suggested.

-powered up and initialised the model
-removed BOTH receivers while the model is still powered

then

-connected only the 9747 to the AIL port

model responds normally

-moved the 9747 to the SAT2 port

model goes to failsafe when the 9747 is removed from the AIL port and does not reconnect when the 9747 is reconnected to the SAT2 port.

I repeated the exact same method with the 4651T and had the same result. I also tried this using SAT1, but again the same results.
It appears that the SAT ports are powering the SRXL2 sats, but no signal is being used from the SAT ports.