Display Degrees of rotation.

[Bobw55]

I think the sensor from the mouse will work. It is the disc that I have to change out. If I can elongate the motor shaft to accommodate the disk, I can have all the pulses I need. It will create the problem of having to figure out how many per one rev of the antenna. Not too much room in the housing accept under the motor. I have also thought about using the hall sensors that are inside a CD drive motor. For me, finding a way to get sensor information from the motor is the easy part. Selecting a PIC and LCD display will be the hard part..
Keep the ideas coming!!!

Bob

[Darrel Taylor]

Just a crazy thought ...

Is the rotor's motor AC or DC?

If it's DC, maybe you could count the commutator pulses from the motor current, and not need an encoder at all.

[Bobw55]

It is 2 phase AC. I thought about replacing it with a DC motor. It would be easier to have the display unit control the motor as well. This is a small TV antenna style rotator. Because the control unit uses TIME to allow for movement, the pointing accuracy can really vary, and you are mechanically locked into a max of 360 degrees of rotation. Once I figure out a digital display, I am going to remove the mechanical stop. I would like to under rotate by 90 degrees and rotate past 360 by 90 degrees (540 degrees total).

Bob

[aratti]

How much power do you pump into the antenna ?

Al.

[Bobw55]

I only run 50 watts through LMR400 cable. I thought about RF interference, But that can be solved with shielded cable and some roids. Going to grab the rotor off the tower today so I can see where I can mount some sort of sensor.

Bob

[Bobw55]

Well managed to get a pulse disc attached to the end of the motor shaft today. Will have pulses a plenty. Starter question would be:

1) What would I need minimum to just count the pulses and display them assuming I am using a sensor from a mouse?
2) I can mount up to a 2 1/2" disc with a fare amount of divisions on it Was thinking 20 to start.

Sorry to ask so many questions.

Bob

[Dave]

Bobw55 , I have to ask, What kind of rotor are you trying to retrofit? There should be some kind of encoding device already inside. The old alliance rotors had a switch that produced about 50 or so pulses. Cant you just use that one for starters?

Dave Purola,
N8NTA