On Wed, 2008-11-26 at 23:00 -0500, Gene Heskett wrote: ... snip > Emc could probably be massaged into doing it, and there would be a > certain cachet to the geekiness of it all when bragging rights are > being displayed to the visiting Joe Sixpacks, but why? It actually > works pretty well as is. :-)
I don't know what Bob wants to use his rotator for, but I wanted to use one to point a weather webcam, so getting the direction fairly close would be good, though not essential. It also has to be computer controlled. The control boxes that I had, did not cater to hacking an interface to a PC, so I decided to have the PC create the 24 Volt "AC" that the original control box put out. I recently got a new rotator and found inside the controller, a microprocessor, relays and transformer, instead of the old synchronous motor. After thinking about it more, since the normal signals are 60 Hz, pointing could be controlled with just a decent control of the amount of time a forward or reverse signal is on. I could reuse the 120VAC to 24VAC transformer and phase shifting capacitor from the original synchronous controller, to create phase A and B. Then use HAL and realtime to output forward or reverse signals with closely controlled on time. I seem to recall that it takes about 20 seconds for a complete rotation, so controlling within .01 seconds, would be close to .2 degrees. The other method above has the advantage of not needing realtime, but for my weather-cam application I need to run some other software (gPhoto, ImageMagik, FTP) so Ubuntu would be running anyway. I just need to find the time to try it. ------------- Kirk http://www.wallacecompany.com/machine_shop/ ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
