steiger@GRUS.CS.NPS.NAVY.MIL (Robert Steigerwald) (03/08/91)
I recently added another 4 Meg of memory to my SE/30 and soon after noted that the monitor started to "flicker". The flickering occurs when the system has been up for a while and is "warm". To be more specific, I get horizontal lines at the top and bottom of the screen that appear and disappear. With each occurrence, the entire screen image jumps slightly. This anomaly is not fatal but it is annoying. Common sense tells me that the new memory has nothing to do with the problem, i.e. this is either a coincidence or I touched something I wasn't supposed to when I had the case open. Are there any Mac doctors out there who have an idea why this is happening? Thanks in advance. Bob Steigerwald
nick@cs.edinburgh.ac.uk (Nick Rothwell) (03/08/91)
Well, I can't help you, but I can tell you that my SE/30 has had this problem twice, and had to be serviced (under guarantee). Then, the vertical sync went completely. I wonder if SE/30's have delicate video circuitry in general? -- Nick Rothwell, Laboratory for Foundations of Computer Science, Edinburgh. nick@lfcs.ed.ac.uk <Atlantic Ocean>!mcsun!ukc!lfcs!nick ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ "I feel a rant coming on." -- John F. Haugh II, alt.folklore.computers
lmui@ora.com (Linda Mui) (03/09/91)
From article <9103080021.AA01201@grus.cs.nps.navy.mil>, by steiger@GRUS.CS.NPS.NAVY.MIL (Robert Steigerwald): > > I recently added another 4 Meg of memory to my SE/30 and soon after > noted that the monitor started to "flicker". The flickering occurs when > the system has been up for a while and is "warm". To be more specific, I > get horizontal lines at the top and bottom of the screen that appear and > disappear. With each occurrence, the entire screen image jumps > slightly. This anomaly is not fatal but it is annoying. We've always had the same problem with our SE/30, and I remember seeing at least one other posting about it on this newsgroup. The horizontal lines appear approximately half an inch from the top and bottom of the screen. Our machine has never been upgraded. Do any other SE/30 owners out there have this sort of flickering? Even better, did any other SE/30 owners out there figure out how to fix it? Please post. -Linda Mui lmui@ora.com
amichiel@rodan.acs.syr.edu (Allen J Michielsen) (03/10/91)
In article <1991Mar8.162541.9578@ora.com> lmui@ora.com (Linda Mui) writes: >From article <9103080021.AA01201@grus.cs.nps.navy.mil>, by steiger@GRUS.CS.NPS.NAVY.MIL (Robert Steigerwald): >> I recently added another 4 Meg of memory to my SE/30 and soon after >> noted that the monitor started to "flicker". The flickering occurs when >> the system has been up for a while and is "warm". To be more specific, I >We've always had the same problem with our SE/30, and I remember >Even better, did any other SE/30 owners out there figure out how to Get a new analog card. al -- Al. Michielsen, Mechanical & Aerospace Engineering, Syracuse University InterNet: amichiel@rodan.acs.syr.edu amichiel@sunrise.acs.syr.edu Bitnet: AMICHIEL@SUNRISE
davisson@milton.u.washington.edu (Gordon Davisson) (03/10/91)
In article <9103080021.AA01201@grus.cs.nps.navy.mil> steiger@GRUS.CS.NPS.NAVY.MIL (Robert Steigerwald) writes: >I recently added another 4 Meg of memory to my SE/30 and soon after >noted that the monitor started to "flicker". The flickering occurs when >the system has been up for a while and is "warm". To be more specific, I >get horizontal lines at the top and bottom of the screen that appear and >disappear. With each occurrence, the entire screen image jumps >slightly. This anomaly is not fatal but it is annoying. > >Common sense tells me that the new memory has nothing to do with the problem, >i.e. this is either a coincidence or I touched something I wasn't supposed to >when I had the case open. > >Are there any Mac doctors out there who have an idea why this is happening? I've never seen this problem on an SE\30 before, but I've seen something like it in other compact Macs. It may be you have a slightly cracked solder connection on one of the lower two pins of the yoke connector (that's the 4-pin connector near the top front of the analog board). Usually it's the top pin that goes first (and then the whole screen collapses down to a thin line), but occaisionally the bottom pin goes, and if the connection is intermittent in just the right way, it can give the symptoms you describe. So try resoldering the yoke connector to the analog board. It can't hurt (well, unless something goes wrong with the soldering) and it might solve the problem. -- Gordon Davisson Westwind Computing (206) 632-8141 4518 University Way NE, Suite 313, Seattle WA 98105
afry@uhura.cc.rochester.edu (Alan R. Fry) (03/10/91)
>Do any other SE/30 owners out there have this sort of flickering? >Even better, did any other SE/30 owners out there figure out how to >fix it? Please post. > > -Linda Mui > lmui@ora.com I had this very problem after I had a Quantum 105 HD installed by the dealer where I bought my SE/30. The screen flickered something fierce whenever the hard disk was accessed. The flickering occurred mostly in the lower part of the screen. The dealer was clueless as to what to do about it, but he tried the hard disk in another SE/30 and it also flickered. I was pretty sure it was the HD itself, so I called and talked to the folks I had ordered it from, and I also called another mail order place to talk to their tech support people. It turned out not to be the hard disk, exactly. What I found out is that stray magnetic fields from the hard disk controller tend to cause some serious interference in the SE/30 monitor card (I don't if the same troubles occur in the SE, Plus, and Classic, but I suppose they do.) The solution was for me to open the sucker up and remove the HD from the bracket, rotate it 180 degrees along the verical axis, and replace it in the bracket. In order to do this, you have to run the SCSI cable underneath the HD, between it and the bracket. It seemed like a pretty flimsy fix, but almost all of the flickering went away. What is left is barely noticable. I have also heard of people who tried to construct Faraday cages (a closed metal casing) for their monitor conroller cards. I hear that aluminum foil doesn't work, but sheet metal does. Be careful with those sharp metal corners in high electric fields. One other bit of experience I had came when I was installing a hard disk in a friend's SE. There was no problem with the disk causing any flickering, but after I installed it, the screen flickered all of the time. What I decided was the I must have bumped the monitor card when I had the case open, so I opened it back up and (with the power off) wiggled the monitor card a little (I can hear Apple Techs screaming). This cured the problem. If you try this, be VERY gentle with your wiggles since the connection to the monitor yoke seems pretty unstable. The root of the flickering problems seems to come from the monitor controller card itself. I don't know how much it would cost to get a replacement, but I would guess it would be a bundle. For that matter, I'm not sure that getting a new one would fix the problem. Hope this helps. Alan
miscord@mullian.ee.mu.oz.au (Michael Scordilis) (03/11/91)
In article <1991Mar8.162541.9578@ora.com> lmui@ora.com (Linda Mui) writes: > >The horizontal lines appear approximately half an inch from the >top and bottom of the screen. Our machine has never been upgraded. > >Do any other SE/30 owners out there have this sort of flickering? My SE/30 has the same symptoms. I have upgraded its RAM from 1 to 5 Megs a year ago, but the flickering appeared only 3 months ago. I don't know if they are related. Also, the SE in my office is flickering after it was upgraded from 1 to 2.5 Meg My guess would be that it is a power supply problem. In my case, when I leave the machines on for a while, the flickering dissapears. Michael > -Linda Mui > lmui@ora.com Michael Scordilis |internet miscord@mullian.ee.mu.OZ.AU ee eng, uni of melbourne |uunet ..!uunet!munnari!mullian!miscord parkville, vic 3052 |fax +[613] 344 6678 australia |phone +[613] 344 6800