JEOL Probe Users Listserver Moderator: Ellery Frahm, [log in to unmask], Electron Microprobe Lab, University of Minnesota Post a message: send your message to [log in to unmask] Unsubscribe: send "SIGNOFF PROBEUSERS" to [log in to unmask] On-line help and FAQ: http://probelab.geo.umn.edu/listserver.html * Steve, I thought the motor shaft had a pin in it. When it flips it rotates 180 degrees until the pin rotates through to the stop. When the motor is called on to flip again it rotates in the opposite direction 180 degrees until the pin comes to a stop. Yes, no? Mike On 5/1/09 4:43 PM, "Steven Cogswell" <[log in to unmask]> wrote: JEOL Probe Users Listserver Moderator: Ellery Frahm, [log in to unmask], Electron Microprobe Lab, University of Minnesota Post a message: send your message to [log in to unmask] Unsubscribe: send "SIGNOFF PROBEUSERS" to [log in to unmask] On-line help and FAQ: http://probelab.geo.umn.edu/listserver.html * Hey probe folks; Here I am again with something that's been bothering me. Our workhorse 733 decided not to completely flip one of the spectrometer crystals during a run recently, it kinda turned the motor half way and gave up. Nobody observed it at the time so not really sure what happened. We turned it back by hand and it's been fine since. That's not what's been bugging me though. I've never had to do anything to those little motor-flip assemblies before, and in looking at them I came to the conclusion that I have no clue on how it actually knows what it's doing. I thought at first "yeah, little stepper motor"... no, only two wires. So it's probably just a DC motor? It has mechanical stops at either end of the rotation travel (this is a two-crystal assembly, so 180 degree flip). How does this silly thing function normally? Does the software just drive it for n-seconds, until it's sure it bumped up against the stop, or does it have some feedback that I'm not seeing? What bugs me is if it just drives up against the stops what keeps it from shredding up it's little gears? Some kind of clutch? Does it ever know if it's misaligned, or what state it's in when it powers up? I'm more and more convinced as the years go on that the mechanics on these machines is purely for show, and it all runs on magic. Beautiful wonderful magic. I took a picture of the fellow here, in case you don't know what one I mean: http://www.flickr.com/photos/stevencogswell/3491352250/ Wish: I want a probe with lots and lots of spectrometers. Have a great day, everyone. Best regards, Steve ******************************************************************** Michael M. Cheatham 312 Heroy Geology Laboratory Phone (315)-443-1261 Syracuse University Fax (315)-443-3363 Syracuse, NY 13244-1070 email:[log in to unmask] http://earthsciences.syr.edu owner of PLASMACHEM-L: http://listserv.syr.edu/archives/plasmachem-l.html owner of XRF-L: http://listserv.syr.edu/archives/xrf-l.html owner of TIMS-L: http://listserv.syr.edu/archives/tims-l.html owner of SIRIS-L: http://listserv.syr.edu/archives/siris-l.html ********************************************************************