Astec AMIX - Multi Motor Mixer

Amix - Multi Motor Mixer

Thank you for buying an AsTec Product. With a little care it will give you hours of good service and enjoyment. To ensure its reliability we have used nothing but the best parts available.

How The AMIX works

The heart of the unit is a micro-controller chip (combination of microprocessor and memory unit all in one). The runs an embedded program that dictates what actions it should take and when. When the unit is first turned on it checks the incoming pulse signals from the receiver. The length of these signals is stored and used as the null point. Once the controller is set up it enables it's output lines and starts the mixing process.

The process follows certain rules:-
Motor output is a combination of speed (S) and rudder (R) settings following rules LM= S-R RM=S+R
S and R are measured with respect to the Null point.
Motor speed can be no greater than normal output (I.e. pulse width is limited to normal RX output) at full speed and full rudder the inner motor will stop at half speed the inner motor will reverse to half speed in the opposite direction and the outer motor will run at full speed
Null point is set a switch on by measuring TX output

There are also pass through ports that provide access to the receiver signals without any processing, these can be used for the rudder servo and for centre motors on triple motor arrangements ( only the wing motors will be mixed). The unit has been programmed to work correctly with most modern two channel outfits. It does expect to see the rudder signal first (channel 1) and then the Speed signal (channel 2). It will work if they are reversed but response may be slowed. If this occurs we can provide and fit an alternate micro-controller. If the returned mixer is brand new and in pristine condition then the cost will be covered by postage. Otherwise please ask what the current charge is.

SETTING UP.

Check the receiver plugs for polarity by matching them up with one of your existing working servo plugs Changes to the wire positions can be made by gently depressing the metal retainer and removing the necessary wires. They should automatically lock in place when re-inserted in the required positions. The supplied plug fits modern futaba equipment with no changes, the plug tabs can be trimmed to fit other models - we recommend the gentle application of a file for this.

Plug the unit in to the receiver sockets as specified ( a servo can be used to check that you have the correct ports - receiver are configured differently so we cannot be of any more help). Plug your speed controllers in to the unit. (Servos can be used for initial set up's if preferred). Turn the transmitter and receiver on in that order. The unit will perform a set up sequence to read and store the null positions etc. This only takes moments.

Now go through the following steps - do not continue to the next step until the one that you are on is correct. To prevent confusion when you make changes only make one change at a time .

Check for correct rudder operation. Stand behind the model facing the bows. Move the rudder stick to the right. The rudder should move to the right (Starboard). If it does not turn off and correct it's movement by using the other side of the rudder arm or using the servo reverse on the transmitter. If you user servo reverse make sure that the mixer is reset by turning it of and back on.

With no rudder use the throttle stick to check the basic motor operation. If the motor(s) run in the wrong direction correct this by swapping the motor leads on the motor terminals.

Set the speed to say 1/4 ahead. Slowly introduce right rudder. The left motor should speed up and the right motor should slow down and eventually reverse. If the right motor speeds up, turn off and either swap the MOTA and MOTB connections on the mixer OR swap the motors between speed controllers.

If you have got here it should all be working correctly.

The unit will theoretically work in any set up—but it prefers to be connected as directed. It is also sensitive to too short RX pulses in combination. If you experience strange results try swapping the rudder and speed inputs.