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I have just installed the JR Tx module into my Taranis, trying to go thru the radio setup. I have set it to the external module, PPM, and it is asking for the frame rate. It is showing 22.5ms, 300u. I assume this is correct? I have not found this addressed anywhere.
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Yes, you can use 22.5ms in PPM mode. You can also use the XJT-D16 if you have our module that supports it. That would give you up to 16 channels available.
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(05-10-2021, 11:29 AM)j_whitney Wrote: I have just installed the JR Tx module into my Taranis, trying to go thru the radio setup. I have set it to the external module, PPM, and it is asking for the frame rate. It is showing 22.5ms, 300u. I assume this is correct? I have not found this addressed anywhere.
(05-11-2021, 01:20 AM)XPS Wrote: Yes, you can use 22.5ms in PPM mode. You can also use the XJT-D16 if you have our module that supports it. That would give you up to 16 channels available.
Would that be this module:
https://www.xtremepowersystems.net/prodd...rod=XPS-J1?
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j_whitney,
That's the correct transmitter module. To support XJT-D16 in the Taranis the Tx module must be upgraded to XPS firmware version v4.4. I've used it successfully on both XJT-D16 and PPM modes.
Good luck,
Paul
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Yes, you can use v4.1 or later of the J1 module firmware. If you have purchased your J1 module in the last 6 months it should already have the latest firmware (which was a work-around for a problem in the OpenTx firmware, that they have corrected with an update to their firmware).
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(05-11-2021, 01:20 AM)XPS Wrote: Yes, you can use 22.5ms in PPM mode. You can also use the XJT-D16 if you have our module that supports it. That would give you up to 16 channels available.
I'm using the JR module with a RM Tx16s. In PPM mode with 22.5ms and 300us, I can set the radio to about 11-12 channels. After that the servo movement gets choppy. Increasing the ms to over thirty will smooth the movement out. I purchased my module this year. I tried the XJT protocol but was unable to get a bind. What is the procedure to use this protocol?
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This is to be expected! You NEED to increase the frame rate any time you add channels. The formula for doing this is:
Number of channels x 2.2ms + 4.7ms.
So, for 12 channels you MUST have the frame rate no less than 12x2.2+4.7 = 31.1ms. If you don't, you can lose part of your data and the controls will definitely become jittery as channels can cross into each other.
You can see that for 8 channels, 8*2.2+4.7 = 22.3ms, and that is what JR and other systems used since PPM was created for 8 channel radios.
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(06-09-2022, 01:24 PM)XPS Wrote: This is to be expected! You NEED to increase the frame rate any time you add channels. The formula for doing this is:
Number of channels x 2.2ms + 4.7ms.
Thanks for that explanation. Still wondering how to use the XJT-D16 protocol? Do I select this protocol in the radio then attempt to bind with the bind button on the back of the radio. Or is it better to just stick with PPM and increase the frame size?
Thanks.
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You have to put the XtremeLink module into "XJT-D16 mode". After that you would set the XJT-D16 protocol in the radio. Once you have done that you can bind just like normal.
You are WAY better off (from a latency standpoint) to use the XJT-D16 mode.