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REX12 And R3/900 and CB200 Set Up

Old 09-22-2019, 03:04 AM
  #26  
CraigG
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Originally Posted by wfield0455 View Post
Craig,

In Default mode both transmitter 2.4Ghz RF sections talk to the receiver alternately and as I recall in double path mode each transmitter 2.4Ghz RF section talks to the Primary and Secondary receivers. In dual double mode, both the Primary and secondary receivers support telemetry telemetry. The 900Mhz is a backup receiver and never even fully activates until BOTH 2.4Ghz (if there are 2) have failed. I'm assuming Danny's recommendation for the REX12 is the longer antenna leads and the different antennas. I'm not 100% certain that they really work any better but I can't say they don't either. The longer leads certainly allow better separation of the antennas which should make it easier to avoid having both antennas shadowed by an object in the aircraft. As for Danny's recommendation to connect the 900Mhz directly to the Rx2 of the CB200 I'm not sure he wasn't recommending that before the CB200 had been updated to allow 2, 2.4Ghz receivers AND an R900Mhz. As I said, I'm not all that big a fan of dual receivers anymore so I certainly wouldn't be concerned about a single 2.4 I'hz RX and a single 900Mhz (I don't use 900Mhz either myself as I have no issues at all with 2.4Ghz). Still, since a Cortex PRo was involved I'm not sure why he didn't suggest connecting the R900 directly to the REX12 and then only the Cortex pro to the CB200. Now that the REX receivers allow a second receiver to be connected via Ex Bus I'm not sure why he didn't suggest connecting the R900 direct to the REX12 or even the Cortex Pro so that you would still get stabilization should the system fail over to 900Mhz. Still since I don't use the Cortex Pro I may be missing something obvious and Danny is the expert with the Cortex devices so I'd follow his recommendations,..
Wayne,
Thanks or taking the time with your explanation and comments! It's interesting that we are so concerned with multiple rx options when in reality, the primary rx's are so good/reliable that we'll probably never experience a condition requiring backup. Think of all the years we flew successfully with just a single rx/antenna and thought nothing of it. Nevertheless, it's nice to know we have some sort of redundancy in the unlikely event of an equipment failure or unusual RF environment, particularly with the 900mhz.
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Old 09-22-2019, 05:40 AM
  #27  
Edgar Perez
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With the expense involved in our models, my preference is to have multiple receivers. The risk you mitigate depends on factors that include how "clean" from a 2.4Ghz your field is, the location of your antennas in your install, etc

The deficiencies on taking advantage of the dual (or more) receivers mentioned above are not because there are more than 1 Rx, but rather the way the selection of signals is implemented in the Jeti systems. where there are multiple Rx.
Other equipment's will receive the signals from multiple Jeti receivers and select on "frame by frame" basis a valid signal. Using that approach, you can then receiver the full value of having multiple Rx's.
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Old 09-22-2019, 07:13 AM
  #28  
wfield0455
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Originally Posted by Edgar Perez View Post
With the expense involved in our models, my preference is to have multiple receivers. The risk you mitigate depends on factors that include how "clean" from a 2.4Ghz your field is, the location of your antennas in your install, etc

The deficiencies on taking advantage of the dual (or more) receivers mentioned above are not because there are more than 1 Rx, but rather the way the selection of signals is implemented in the Jeti systems. where there are multiple Rx.
Other equipment's will receive the signals from multiple Jeti receivers and select on "frame by frame" basis a valid signal. Using that approach, you can then receiver the full value of having multiple Rx's.
While it's true that other devices such as the XPS24 and I believe Power Box will look at multiple receivers on a frame by frame basis we were discussing an REX12 with a clone. Unless there is a firmware update that I'm not aware of (very possible) devices such as the Cortex Pro duplicated the way Jeti looked at dual receivers and not on a frame by frame basis. Also I never said multiple receivers caused a problem, only that the Jeti implementation does a very marginal job of providing the antenna diversity that multiple receivers should provide. I never told anyone not to use them, I simply explained how they work and the short comings. It's a personal choice and as long as someone understands what they are getting then great, they should add whatever they want to their models..

Last edited by wfield0455; 09-22-2019 at 07:19 AM.
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Old 09-22-2019, 10:39 AM
  #29  
Jack Diaz
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The V1.32 CB200 firmware, has a switchover strategy named "Mixing", which means that the CB combines data from all active receivers in a packet by packet basis (as long as the receivers are connected to the CB via EX Bus).
What is interesting about this, is that it does provide antenna diversity since the signals from all the antennas are processed at the same time.
I think that none of the receivers can be an Assist rec.

Upgrading to V1.32 may require upgrading the transmitter Devices folder.

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Old 09-22-2019, 10:53 AM
  #30  
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V1.32 also includes the possibility to reduce the switchover time from 150 to 80ms.

I guess that is the strategy to follow if one of the receivers is connected to the CB via a CortexPro


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Old 09-22-2019, 11:23 AM
  #31  
CraigG
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Originally Posted by Jack Diaz View Post
The V1.32 CB200 firmware, has a switchover strategy named "Mixing", which means that the CB combines data from all active receivers in a packet by packet basis (as long as the receivers are connected to the CB via EX Bus).
What is interesting about this, is that it does provide antenna diversity since the signals from all the antennas are processed at the same time.
I think that none of the receivers can be an Assist rec.

Upgrading to V1.32 may require upgrading the transmitter Devices folder.

Jack
Thanks for the information Jack. The Espiritmodel website shows V1.20 as the latest CB200 firmware and jetimodel.com shows V1.31. Where do we find v1.32?

Thanks,
Craig
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Old 09-22-2019, 01:21 PM
  #32  
Edgar Perez
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Originally Posted by wfield0455 View Post
While it's true that other devices such as the XPS24 and I believe Power Box will look at multiple receivers on a frame by frame basis we were discussing an REX12 with a clone.
I think you did an excellent description of the situation the OP asked about. Just wanted to highlight that we should not give up the redundancy protection possible with today’s available options.
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Old 09-22-2019, 03:15 PM
  #33  
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Originally Posted by Edgar Perez View Post

I think you did an excellent description of the situation the OP asked about. Just wanted to highlight that we should not give up the redundancy protection possible with today’s available options.
I think Jeti does a good job at least for me with my electric’s and jets both at home and at event’s, never did miss a beat...at least for my models I don’t need anything else.......all these suppose to be better then this and that...are just that suppose to be better....
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Old 09-22-2019, 04:45 PM
  #34  
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Originally Posted by CraigG View Post
Thanks for the information Jack. The Espiritmodel website shows V1.20 as the latest CB200 firmware and jetimodel.com shows V1.31. Where do we find v1.32?

Thanks,
Craig

Sorry Craig, I meant V1.31
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