It has been fun to watch this thread. Assuming this is not a plasma or lcd display and since you have found out that lowering the refresh rate to 60 solves the problem, we can assume that this is a power issue. (Unless you live in Europe then we have another problem ;) ) A CRT screen is extremely sensitive to a magnetic field. That is why you will always find a degauss button or function on the monitor. This button applies a charge to a ring around the picture tube degaussing the tube, giving it a much cleaner image (and one that doesn't shake as bad).
These screens are very sensitive to magnetic fields (magnets or magnetic fields created by electricity or electrical energy). The circuitry is also very sensitive to RF energy (that created by transmitters as small as cellphones, microwaves, PLC's, the list goes on). But RF energy is not constant like electrical interference. When the microwave quits running then the problem will go away etc. That is why I think that yours may be more related to electricity or a magnet pull (AC in high voltage lines over the house can create a magnetic looking problem as well.) If you have a high voltage line over the house you may want to consider harnessing that energy by (aaaah, nevermind that thought is illegal anyway) The first comment you mentioned is probably the best one you have. Put a choke (ferrite core) around the signal cable on the monitor. It may already have one or two (big fat round things close to the end(s) of the cables). If those are there, then you may consider putting one of those on the ac cable as well. (5-7 tightly wrapped turns around a medium size ferrite core will get rid of any signals on the power line you have coming through). Many power supply circuits are not designed well enough to remove strong signal problems on the ac line so that may be an option. In the meantime you may want to keep an eye out for something electrical close by. As for the UPS, try running on the UPS and kicking the main breaker off in the house and see if it goes away. These are really fun to find. Good Luck.. Doug -----Original Message----- From: Roland Roberts [mailto:[EMAIL PROTECTED]] Sent: Tuesday, February 11, 2003 11:16 AM To: [EMAIL PROTECTED] Subject: Monitor Shakes.... -----BEGIN PGP SIGNED MESSAGE----- Okay, this has *nothing* to do with RedHat per se except as a pure coincidence that I happen to be running RH 8.0 on the machine. After moving into a new home, my monitor has developed this odd "quiver." There are these slow undulations in the screen that are there even if everything else in the room (everything except the computer and the monitor, that is) is turned off. They even continue to appear when I pull the UPS out of the wall so everything is running of batteries instead of wall power. The monitor refresh is at 65Hz. I can use xvidtune to modify the frequence down to 60Hz at which point the undulations disappear. Looks like a beat problem with the line frequency. My wife's iMac has the same problem except I can't change her refresh rate to eliminate the quiver. Anyone have any clues how I can eliminate this apart from the refresh rate? I've had one person suggest putting a choke on the signal cable, and I'm going to try that. Any other ideas are welcome. TIA, roland - -- PGP Key ID: 66 BC 3B CD Roland B. Roberts, PhD RL Enterprises [EMAIL PROTECTED] 6818 Madeline Court [EMAIL PROTECTED] Brooklyn, NY 11220 -----BEGIN PGP SIGNATURE----- Version: 2.6.3ia Charset: noconv Comment: Processed by Mailcrypt 3.5.4, an Emacs/PGP interface iQCVAwUBPkkhvuoW38lmvDvNAQE0vAP6A2WvZtvXQksthKEVmyfdo/JSBjyOx5gA HU/3Z/RHe417EEu9y2/AiBF5Bufo2fEy+810ee7dE0TKUogedMr4kWev/m4JVz9d XFJQZJG0yMqUVkjrOLA9fD9RhPh+/4JRcWckAbjdO8084pndFUT2XiSIFhHziUlw 32C/ZcDUq2Q= =BOx1 -----END PGP SIGNATURE----- -- redhat-list mailing list unsubscribe mailto:[EMAIL PROTECTED]?subject=unsubscribe https://listman.redhat.com/mailman/listinfo/redhat-list -- redhat-list mailing list unsubscribe mailto:[EMAIL PROTECTED]?subject=unsubscribe https://listman.redhat.com/mailman/listinfo/redhat-list
