Is it possible to control a digital potentiometer from the aux motor outputs of a trex jr? How would it be connected?
No, it does not seem likely that the auxiliary motor output on the TReX Jr can do that. The aux motor output is basically a power supply voltage that can be switched on and off. While it might depend on the particular digital potentiometer, I suspect those devices require some kind of digital input (or inputs) and use an interface like serial or I2C.
Thank you for your prompt response. I’ll have to come up with something else. I’m attempting to use the Trex Jr. to control the pan/tilt and zoom of my video camera via RC.
The pan and tilt motors are controlled beautifully by the Trex, and I was hoping to control the zoom via the aux output. What I need for this is a variable resistance from 0 to 20k ohms. I may be able to use a 0-2 volt circuit instead.
Currently, the speed of the aux output motor does not correspond linearly to my input signal. It starts out fast, slows to almost a stop at mid range and then speeds up again at the high end. For a voltage controller to work with my zoom circuit, I need a linear response. Is this an issue with the channel configuration settings?
Can you try calibrating channel 3 so that the value of the neutral position is the same as either the minimum or maximum position? Since the auxiliary motor is unidirectional, setting the neutral position in between minimum and maximum will cause the behavior you described.