JR 921 receivers

[Bartman]

no setting in the JR9503 that I can find but in the DSMX DX8 there is a "Frame Rate" setting and included in that is a DSM2 or DSMX setting.

now i'm confused too

 

[Phil.Griffin]

Ive flown dsmx rx on dsm2 TX and vise versa. No issues. The radio detects 2 or x itself. There is NO user setting in the Tx.

You must have minimum 1 remote ant plugged into the rx. If you unplug that remote rx and reinstall to another port, you must rebind.

A good battery should be used as well. Like mentioned above, you probably have something flipped wrong, tie servo end plug into the rx.

Correct ..
DSMX transmitters are fully backwards compatible to DSM2. I have two, 11x's. One has been upgraded to "X" and the other has not. I've used them both with both protocols without issue.

 

[ryan_m]

frame rate is not dependent on the radio protocol. To support the faster frame rates you have to have servos capable of it, as well as an rx capable of it. The default is 22ms. Frame rate was all the rage a few years back, and from what I can remember really only the heli guys were able to supposedly notice much benefit from it. Supposedly it was less latency (servos move quicker when you move the sticks). The 9503 is a 22ms frame rate only, it's an older radio from before anybody cared about that. Spektrum/JR came out with a DX7-SE that was a faster frame rate capable radio, and then the Spektrum DX8/DX9 began being capable too I think.

I used to have a 9503 and had no problems running either DSM2 or DSMX on it. It would automatically bind in whatever the rx supported. The only way I even knew how to tell which it used is to power off the rx while leaving the tx on. Then power the rx back on, and if the light blinks it's probably a dsm2, and the blinking light indicates that it lost power, while the tx didn't. Useful to know if you have a power issue in flight.
On DSMX however this doesn't work as it's implemented by check the last two transmitted frequencies and if the tx is still operating on them then it knows the tx never lost power. On DSMX it channel hops all over, and so it can't check the last two frequencies, and thus the flashing light tattle doesn't work.

Check to make sure your servo polarity is right. The diagram on front shows you which way it goes. If memory serves one of the rx's has the pins opposite the normal way that almost all other Spektrum RX's use...

 

[BarracudaHockey]

Do you have a DSM2 satellite rx? You can't mix and match.

On the 93/9503's there's no menu for protocol, it tries to bind in DSMX, if the rx doesn't respond it switches to DSM2

Also, the remote cables are a weak spot, try a different remote cable and I'd have to look at the 921 to recall but if there's more than one remote rx plug, try it in the other, it might need a certain one present and the other one is optional.

 

[Hoosier06]

frame rate is not dependent on the radio protocol. To support the faster frame rates you have to have servos capable of it, as well as an rx capable of it. The default is 22ms. Frame rate was all the rage a few years back, and from what I can remember really only the heli guys were able to supposedly notice much benefit from it. Supposedly it was less latency (servos move quicker when you move the sticks). The 9503 is a 22ms frame rate only, it's an older radio from before anybody cared about that. Spektrum/JR came out with a DX7-SE that was a faster frame rate capable radio, and then the Spektrum DX8/DX9 began being capable too I think.

I used to have a 9503 and had no problems running either DSM2 or DSMX on it. It would automatically bind in whatever the rx supported. The only way I even knew how to tell which it used is to power off the rx while leaving the tx on. Then power the rx back on, and if the light blinks it's probably a dsm2, and the blinking light indicates that it lost power, while the tx didn't. Useful to know if you have a power issue in flight.
On DSMX however this doesn't work as it's implemented by check the last two transmitted frequencies and if the tx is still operating on them then it knows the tx never lost power. On DSMX it channel hops all over, and so it can't check the last two frequencies, and thus the flashing light tattle doesn't work.

Check to make sure your servo polarity is right. The diagram on front shows you which way it goes. If memory serves one of the rx's has the pins opposite the normal way that almost all other Spektrum RX's use...

When my 9503 did not bind to a 921 it was usually the case that the servo wire was put into the receiver the wrong way. I agree with the above post.

 

[Red Raider]

Seems like the polarity issue is the most logical answer. I'll have to figure out what I was doing wrong, because I did it consistently on multiple trials with 2 different receivers. I'll bet it's in the control box for the retracts. I'll check and let everyone know. Could be a learning experience for all of us.

 

[slowgto]

If it bound fine than that's not the issue. Make sure the servo is plugged in in the correct direction, if it does not work reverse it and see if that fixes it.

What @BarracudaHockey said as well. You can't have DSMX sat's with a DSM2 receiver.... but if it bound life should be good.

 

[Red Raider]

Still haven't resolved this issue. hmmmm

 

[Bunky.F.Knuckle]

Still haven't resolved this issue. hmmmm

Can you post pics of the Rx and the remote Rx's. Something sounds fishy.

If we can't figure it out here, I will PM you my address and I will take a look at it. I've got an 11X here on DSM2.

 

[Bunky.F.Knuckle]

no setting in the JR9503 that I can find but in the DSMX DX8 there is a "Frame Rate" setting and included in that is a DSM2 or DSMX setting.

now i'm confused too

That is 2 different radios, Bart. 2 different manufactures. Spektrum was first on the map with 2.4. JR wanted in the game as well. Spektrum allowed JR to use their protocol.