Hello,

After building a couple of electric singles, I'd like to try and tackle an electric twin.

My question is this:

I'd like to use one channel as a master throttle and another as the trim (speed offset) between the two engines.
Does anybody know how to do this?

Regards

With most any computer radio:
Slave another channel to the throttle channel (I use Ch8, Link on, Trim On)
Make a P-Mix, Master = throttle channel 2, slave same. Assign to a knob or slider. Adjusting the knob/slider will vary the speed of the second engine.
Futaba has a FAQ that may help also:
http://www.futabarc.com/faq/faq-9c-q511.html

Fritz

Depending on how you wire your motors and assuming the motors are essentially identical, you should not need to adjust them independently. Are you trying to remove a beat pattern at a particular throttle setting? Are you using a single controller, or one for each motor? Due to slight variations in motors, prop loads, throttle curves, etc. it can be virtually impossible to perfectly sync both motors at all throttle settings. If you have a separate control for each motor, then the master/slave program will probably work for what you want... but it seems unnecessary to me. If you want to steer or adjust trim using differential thrust... that's a different matter.

-David

I am by no means an electric whiz, but if you are into multi's welcome aboard. One of the thoughts and advantages of electric is lack of engine failure. I also understand that wiring the motors in series increases the reliabilty, but not sure if that is possible with brushless motors. One more crash and I may join you in electric.
Good Luck,
Twinman
Steer with engine thrust........naw!!!

Charlie:

Brushed motors can be run, with either series or parallel wiring, from a single ESC, operating from a single channel. Brushless motors must have one ESC per motor, and they can still be operated from a single channel.

With one ESC per motor, whether brushed or brushless, you can use one channel per motor.

Bill.

you can wire two brushless motors together. with a Kontronic FUN contoller. quite common in twinjets and twin stars. both of which are muliplex ARFs.

Let me add just one thing about brushless motors needing separate ESC's. Brushless motors can not be wired in series, but it is possible to wire two brushless motors in parallel to a single (suitable) controller. Not all brushless motors/ESC's work well this way, but it can be done. Kontronik controllers seem to work best for this task, using Kontronik or Aveox motors. Dedicated motor/ESC pairs are more goof-proof, but there are other options.

-David

EFSIG-IMAC-E-learner types faster than me.

-David