Jeti Duplex Telemetry Useful Ideas & TipsFlight Team Jeti USA

Jeti Duplex Telemetry Useful Ideas & Tips

Central Box 200 with two satellite receivers Step-by-step process for setting up. This is the setup recommended for your high-priced planes as it provides the greatest degree of protection against failure of either Tx module, receivers, batteries, or servos.

two independent systems (redundancy of Tx and Rx)
isolation between the two batteries plugged into the Central box
overload protection (shut off power to failed servo)
additional telemetry from CB (power used, temp, etc)
antenna diversity (you have four antennas) and can see their signal strength.

added cost of the Central Box and a second battery
signal loss on one receiver blanks the displayed antenna strength/quality readout for both receivers (bug - hopefully will be fixed in a firmware update.

With previous setups (eg Dual Path - Dual Receivers - Dependent - Normal per http://www.rcgroups.com/forums/showthread.php?t=2095171) where both batteries were plugged into one of the receivers, there was no power isolation and a failed cell in one of the batteries would pull down the voltage of the other battery. The Central Box provides isolation between the batteries which eliminates this failure mode. Additionally, the CB can shut off power to a servo should it overload/jam/fail.

I started with a transmitter in firmware rev 2.22, I updated the firmware in the Central Box (using the instructions in Section 6 of the CB manual) to firmware version 1.11, and had two R3/RSW receivers with firmware version 3.13.

This procedure will use two R3/RSW receivers. Other receivers (eg R5L) can be used but the output ports and firmware version required may be different. Also, the R3/RSW's will communicate to the CB using the EX Bus as this is a better communication method that PPM.

OK, here we go....

1) Configuration/Binding history
When using the EXT Bus configuration, the servo wires from the CB200 Sat1 and Sat2 ports are plugged into the EXT ports of each of the two R3/RSW receivers. If you have never previously bound the two R3/RSW receivers to your Tx, you will have to bind them with the bind plug in the receiver EXT port. This makes the procedure a bit more complicated and you need the spare battery (with the male JR connector).

2) Bind each R3/RSW to the receiver for the first time.
- In Advanced Properties -> Wireless Modes/Trainer, set the mode to Double Path
- Scroll down to "Alarm at:" and set the pulldown to Loss of any receiver.
- insert a bind plug into the EXT port of the first R3/RSW. Plug the lead from the spare battery into another port of this receiver (make sure you get the right polarity)
- Scroll up to Pair primary TX module. Press select. The transmitter will see the receiver and ask if you want to use it. Press yes.
- Unplug the battery and bind plug from the first R3/RSW and set the receiver aside. The transmitter will alarm "signal lost" when you remove power from the R3/RSW. The alarm will continue to go off - yes, it's annoying, deal with it.
- Insert the bind plug into the EXT port of the second R3/RSW and plug the battery into another port of this receiver.
- Scroll down to Pair secondary TX module. Press select. The transmitter will see the receiver and ask if you want to use it. Press yes.
- Unplug the battery and bind plug from the second R3/RSW.

3) Connect the CB, switch, R3/RSW's and battery as shown in Figure 12 in the CB200 manual. Make sure you get the polarity correct and plug everything into the correct ports.
- turn power onto the CB 200 using the magnetic (or other) switch. The transmitter will link up with the receivers and the "signal lost" alarm will mercifully stop.
- just for fun, plug a servo into one of the servo ports of the CB200 (such a throttle, which I have on port 1) and move the stick. You'll note that the servo doesn't move. This is because you haven't yet configured the R3/RSW's to output in EX Bus mode.

4) Use Device Explorer to Configure the two R3/RSW's and the Central Box
- In Model -> Device Explorer you should see "R3 EX" twice in the list. Scroll to the first one and select
- change the output mode to EX Bus. The Tx will ask if you want to apply changes, press yes.
- set the output period as "Auto", scroll to Failsafe, select, and scroll to disable the fail-safe. Press ESC twice to take you back to the Device Explorer
- Notice how the Device Explorer listing now shows a "CBO200" below the upper "R3 EX".
- Scroll down to the bottom "R3 Ex" and press select.
- set up this second R3 like the first R3 (output mode to EX Bus, output period as "Auto", Failsafe disabled). Press ESC twice to take you back to the Device Explorer
- Scroll up to the CBO200, and select. This takes you to the Central Box 200 screen to set up the Central Box as follows:
- Scroll to General Settings, select, set output period as "Auto"
- Scroll to Expander Settings to set the configuration of the Ext 1 port to "Jetibox"
- If you want to use CB port 14 and 15 to connect servos, change their setting to "Servo output". If you want to use these ports to connect telemetry sensors, change the setting to "Telemetry input". Press ESC to take you back to the Central Box 200 screen
- Scoll down to Fail-Safe, select
- Scroll down to Fail-Safe, select, and change the value to "Enabled", select
- The screen populates with a setting for failsafe delay (I keep it at the default 1.5 seconds) and the Output pin values for all the CB200 ports. This is where you set your failsafe values. All ports should be preset to "Hold" which is the default.
- Scroll down to the channel for throttle (mine in Outpin 1), select, change the mode from Hold to Failsafe, select, scroll to Value and set the value (assuming you know the value you need to shutdown the turbine). If not, you can set this later.
- Press ESC to take you back to the Central Box 200 screen
- Scroll down to Servo Output Mapping, and press select. This takes you to the CBOX200 Outputs screen where you can set up what function you want assigned to each port. If you don't need to make any changes, press ESC
- You can have a look in the Telemetry and Telemetry Min/Max screens if you want.
- Press ESC four times to take you back to the main screen

5) Test the Setup
- plug a servo into one of the servo ports of the CB200 (I used port 1 for throttle). Move the control for that channel (in my case, the throttle stick) and the servo moves accordingly.
- disconnect one of the R3/RSW receivers. You should get a signal lost alarm. Reconnect the R3/RSW. The transmitter should link up with the receiver and the alarm should stop
- disconnect the other R3/RSW receiver. Once again, you should get a signal loss alarm. Reconnect the R3/RSW and the alarm should stop.
- turn off the Central Box using the magnetic (or other ) switch. You're done.

Fuel Consumption Monitoring for Jets!!!
This is a very interesting article from the Jeti site that is of interest to jet modelers as to how to use the MUI 30A Current/Voltage sensors to monitor fuel usage by monitoring the fuel pump consumption as the amount of energy consumed by pump and amount of pumped fuel is linear.

Great usage and imagination in the use of the Jeti Duplex telemetry!!!
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Alarm for in Flight Turbine Shut Down!!!
If the fuel pump draws 0,8-1A at idle rpm and the alarm trigger is set to <0,5A. If the ECU shuts down the fuel pump for any reasons, you get an audio warning "Warning, Flameout!" (Custom Sound for Example). Then you will know in an instant something that you usually need a few seconds, if not more, to realize and potentially safe your very expensive model.

The amp-draw information from the MUI 30A Current/Voltage sensors can be used as a flameout warning. Always easy to hear when others are flying around you.
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Receiver Update:
Update of the receiver

Sensor Update:
Update of the sensor