On Saturday, November 05, 2011 10:07:40 AM andy pugh did opine: > On 5 November 2011 12:09, Viesturs Lؤپcis <[email protected]> wrote: > > I have a suspicion that this might be something connected with Mesa > > card and magnetic field from VFD and also spindle motors, because > > there is CRT monitor ~0,5m from spindle motor and the picture gets > > creeped. It is good as soon as motor is turned off and gets creepy as > > soon as it is turned on. The pattern of creepiness changes as the > > motor moves. > > I would try to get a line filter installed on the VFD supply as a > first stage. That probably isn't the problem, but it sounds like it is > required.
That is more than likely magnetic radiation from the motor, combined with a CRT that isn't running at maximum beam voltage. They can get pretty sensitive. I don't recall seeing that effect on my own machine, but the closest the monitor ever was is nearly a meter and the motor is only about a 2 amp/90 volt motor. Years ago, I was using 2 monitors on a TRS-80 Color Computer 3, and with the monitors sitting side by side, the 12" amber screen and the 15" Magnavox 8cm515 interfered with each other quite noticeably due to the differences in their vertical scan rate. A sheet of aluminum between them helped more than a sheet of steel, but I somewhat got used to it. I was probably one of the two in the world that did that. Two monitors with independent feeds on a coco sure impressed the PC folks. :-) BTW I still have that machine, its running in the basement right now. But now I log into it with either putty or minicom. Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) My web page: <http://coyoteden.dyndns-free.com:85/gene> <WildTHing> ok guys .. so whens the next commit :PP <taniwha> when they come to get me ------------------------------------------------------------------------------ RSA(R) Conference 2012 Save $700 by Nov 18 Register now http://p.sf.net/sfu/rsa-sfdev2dev1 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
