Hi ya there
First of all - as already has been suggested we do really need to know what type of boat the mix is going to be fitted in; but here are a few things for you to ponder over ..
With the new age of this 2.4 style radio stuff there are mixer functions already built into the programmes, allowing you to mix several channels. The way I grasp this technology of the 2.4 programming is you still require to use 3 channels of your radio. Two throttle channels to be mixed plus the 3rd one for your rudder. So you are tying up 3 channels in your radio set.
The other options are to buy a mixer unit; dedicated for marine use - not one of these Y tale mixer thingies, although they are supposed to be pretty good. But, if you go and purchase a dedicated marine mixer from a guy not too far from here who now and again steps into ACTion... you will find with these mixers you only require 2 channels. You will still get full mix on both motors, with 1 stick on your throttle. Now there is a newish unit on the market the 94, which incorporates 2 speed controllers and a mixer in one small package. Now this unit, inside, has several programmable switches and depending on how you set the switches up on the inside, you can have a mix when the boat is stationery where when you move the rudders from port to starboard, it naturally kicks in the motors to mix, even though you havent moved the throttle stick.
If you switch to the other set up with the switches, when you move the rudders port to starboard nothing happens until you move Also, there is a facility for adding a 3rd speed controller for triple motor setup.
aye
john e
bluebird