Hi fellas!
I am having difficulty in finding out how to set/program dual throttles (with dual curves) in my new 10X. I'd like to know how to set this up correctly so I can get my OV-10 Bronco setup. With the 9303 I had, setting this up was a breeze... On the 10X....JEEZE!
I've gone through the documentation but can't seems to find it.
Any help would be GREATLY appreciated. THANKS!!!!!!!!!!

I would suggest asking this question in the "ask Dannyat JR" section of the radio forum. That's where I got help.

osxpro,

I was looking into Jr recently. It just so happens not too long ago I figured out twin programming for a friend with one. First decide what features you want. The minimum I want is to be able to “hold” either engine at idle while the throttle stick runs up the other. This makes mixture adjusting on the ground easy and allows practicing single engine flying in the air.

Every radio brand’s programmable mixers work a little differently. The Jr Pmixers work very simply. The 2 basic Pmix concepts are slaving one channel to another and holding or freezing a channel from responding to its Tx control input. Then build up whatever functionality you want from these 2 basic applications. There are many possible arrangements.

Switch assignability is where Jr falls short. They still haven’t made all switches and switch positions available for any function, like the other brands do. They took a big step in that direction with their new 9, but still didn’t go all the way. The ability to turn features on/off is what makes add on features selectable during flight. The number of switches available limits the number of features that can be independently selected. So with that said Jr gives you only these choices (with flight modes off): E-F, M-D, L-D, MX, AU, GR, SNP, STK. Basically any position of the flap switch, only the top position of the Aux2 switch, the mix switch, and the gear switch. Other brands give every position of any switch – much more flexible! This is the only limitation holding me back from buying Jr.

Here is a simple twin throttle setup where engines can be throttled together or individually from the main stick. For simplicity I’ll use the gear channel (ch5) for the left engine and the main throttle (ch1) for the right. The gear switch will control the left engine operation and the mix switch will control the right. Another channel must be used for gear (alternately the engine control could be put on the 3 position Aux2 switch where up gives both engines, mid left only, and down right only):

Step one is to program the main (right) throttle channel (ch 1) with a hold. For Jr, to hold a channel, just mix the channel to itself, set mix values at -100%, then set mix offset for hold position desired. Select one of the standard (non multipoint) Pmixers. Input ch1 as master and slave. Choose the mix (MX) switch in the switch selection submenu. Set mix both values for position one (Pos1) -100%. Leave Include and Origin off and Trim on. Basically the throttle is now mixed to itself in reverse canceling out its own input. Flip the gear switch and the throttle servo will stop responding to the stick. Changing the Offset changes what position the servo will hold at. Note, if you want to reverse the direction to flip the switch for hold, return Pos1 mix values to zero and set Pos0 values at -100%.

Next, set up the second throttle. Adjust gear channel so it switches the left engine from idle to full throttle. Then adjust the full throttle ATV to zero, so gear switch commands idle and servo centered. Activate a second Pmix with throttle Ch1 as master and gear ch5 as slave. Choose the gear (GR) switch in the switch selection submenu. Leave the Offset at zero (center stick), Include and Origin off, Trim on. Flip the gear switch to mid throttle. Set whichever mix value comes on (Pos0 or Pos1) to -100% each way. So basically when the gear switch is one way the mixer is off and the left engine is at idle, the other way the gear channel is centered and slaved to the main throttle.

The setup I programmed had more features like differential throttling with rudder control and an auxiliary throttle instead of fixed hold position, so was more complicated. There may be a problem with zeroing out the ATV in one direction, for this simple program. It might not allow the slave mix to drive the gear channel to full position. But this is enough to give you the basic ideas and get you going. The rest is just play with these ideas till you get what you want.

Let me know what you come up with?

Multiflyer

This concept works for any radio. I have a futaba and mine will do the same thing. I was looking at using another channel for right throttle but never thought about mixing it to itself inversely on a switch.

Thanks for the insight.

Yes, the idea works basically the same for all radios. The Pmixes behave a little different. The biggest difference is the switching availability. Futaba is the best here. All switches available however you want. Just wish they would provide more Pmixes. Haven't had time to study their new 14 channel yet. Hopping they provided enough Pmixes to to do great things with all those channels? Pmixes get used up fast when building custom features. Airtronics Stylus is as good if you get the additional feature upgrade card. Multiplex is the worst. They offer a 12 channel radio. The channels can be assigned to any Tx input. This gives great basic setup flexibility. The problem is these assignments can't be switched on and off. No way to throw control from main throttle stick to an auxiliary throttle during flight for example. They do give programmable mixes that can switch controlled and used to do this. But basically all their switchable features are assigned to a "virtual" switch, then the virtual switch is assigned to an actual Tx switch. They only give 3 virtual switches! So only 3 different things can be on/off controlled during flight. I can't wait for the day when someone will offer a big fat number of channels and a computer interface to let me program it however I want without limitations.

Multiflyer

Another example is to setup the left and right engine on the left and right side lever controls. Add 2 P mixes to each. The first Pmix mixes the channel to itself (-100%/-100%) to cancel out the lever input. Leave the offset at zero, Include and Origin off, Trim on. This parks the servo at center. Use the second Pmix to slave to the throttle stick. Assign all 4 Pmixers to the mix switch. Result is Mix switch on, both channels respond to the throttle stick only, moving side levers has no effect. Mix switch off, both channels work by their respective side levers and the throttle stick has no effect. The Pmixes for each channel could be assigned to separate switches, so control could be transferred individually.

This example illustrates why lots of channels, lots of Pmixers, and unlimited switch assignment flexibility, are is so important for building scale features. Other nice features are differential throttling via the rudder – requires 2 more Pmixes and another independent switch, 4 Pmixers if you want it to work at high and low throttle. A 4 engine plane would need 4 more Pmixes and 2 more independent switches. I lke to put my nose or tail wheel steering on a separate channel then slave to the rudder. This way I can change trim of each without disturbing the other and shut off the wheel steering when the gear is retracted eliminating the need for linkage that can handle the steering movement gear up. Also like to have 2 rates on just the wheel, very high for taxi and low for takeoff and landing. So wa are talking 2 more Pmixes and another independent switch. I like to use the multipoint throttle curve to program a small dead band at the bottom of the throttle stick movement. Then go into the transmitter and modify the spring return to apply pressure just above the dead band. So throttle works normally from full to idle but there is a little bit more movement against the spring for activating air or wheel breaks.

The possibilities go on and on. The limitation of the current generation of radios available are still quite large. Basically they are just getting capable of doing these things. Problem is they can't do more than about one or 2 of them together. Bummer.

Multiflyer