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All things pertaining to wireless and RF links
By geb
I'm new to all of this. I'd like to find a plug/play solution to a dead simple need.

I need to adjust a dial (usually rotated by fingertip) on a machine that delivers air from 0 to 10L/min , remotely, RF preferably, with a small hand-held remote that would ideally have a single dial on its face. No more.

The remote radio dial emulates the rotation of the servo driven knob on the machine. Clockwise and counter. The driven knob/dial rotates approx 270 degrees. Torque requirements are low... in the range expected of a finger turned knob on a stereo volume control (for instance).

Any suggestions?
Break this project into several parts.
1- mechanics to drive the flow value.
2- Control dial, Pot, rotary encoder, etc. and how to read its value/position.
3- Data transfer protocol. A serial data steam is a good method for when the RF link is added. Does there need to be error checking (CKSUM)?
4- connect the above three pieces into a working system with a hardwired connection.
5- The very LAST part is the RF link hardware and and required software. If it doesn't work in step 4 then this step will never work.
Five steps. Am I overlooking the complexity of this?

I don't understand why I cannot source a simple rf remote actuated servo motor with a dial controller that simply turns the servo. I does not need to be NASA precise. It does not need to be programmed as far as I can see.

If the servo motor is driven by the remote dial I would just get power to the components... battery in the remote and wall-wart source for the servo motor... and then mark the remote dial with a marker to correspond with the degree of movement of the servo.

As a "newbie" am I wrong to presume something so simple must exist?

In my web searches I've come across wired "test" boards...
that do what I describe.

So why can't I find an RF equivalent to this dead-simple test board? Just a handheld RF remote, with a dial, that does the EXACT same thing as that wired test board. I can deal with the equivalence after it's connected and functioning. Just get the components communicating, and then mark off the settings with a sharpie on the remote that correspond with the degrees of movement of the servo.
If the link you posted is the closest you have come to the hardware you need, then you will need to build this yourself. Since you have the circuit for controlling a servo with a pot, then all you need is to incorporate the RF. You need to find out what kind of signal controls the servo in this circuit, then try to send that signal wirelessly.

And yes, I think you have overlooked the complexity.