[rescue] Sun 21" CRTs (was: Feedback on Sun 24" LCD?)

Rick Hamell hamellr at gmail.com
Tue Jul 8 09:48:42 CDT 2008

> Sure enough the microwaves were smack-dab on the other side of the wall
> from the monitor.  We moved his monitor to the other side of the cube and
> he never had a problem after that.
> I think that was one of the things that taught me to always look at the
> environment first before diagnosing the computer. :-)

I've had some real similar problems in the past.

A mom and daughter plastic manufacturing plant that made things like 
brochure holders and specialized shelving for display units. The mom and 
(very hot but dumb as a brick) daughter shared a smallish office. The 
daughter's monitor would just wiggle, go blank, have red spots at random 
times during the day.

After several days of troubleshooting it, I finally actually got to see 
the problem and realized that it resembled the dieing monitors that we 
put magnets on to "fix" in high school. Searching the building I found a 
small janitorial closet with an electrical panel in it that was right 
behind her monitor.

We talked about it and decided that due to the cramped space in the 
building that moving the computer just would not work. The discussion 
moved around to how to stop the EMF, and moving the panel itself was 
looked at very hard. I then remembered that next door was a heating duct 
  manufacturer. The mom went next door and came back a few minutes later 
with two guys toting a 6x8 piece of sheet metal. They screwed it to the 
wall and like that the problems went away.

On the next visit the daughter had covered that piece of metal with 
magnets holding pictures of her and her friends.

The same place also had another EMF problem with a piece of BNC cable. 
They had a CNC station that cut the plastic parts up. Nearby was an air 
compressor that was used to blow all the plastic shavings off whatever 
project they were working on.

Unluckily the air compressor was somehow not grounded properly. When 
ever it went on the CNC computer would loose network connection and 
would need to be rebooted. Tracing the cables I found that the network 
cable was running under the power cable on the compressor. So in a bout 
of madness me and one of the guys there rerouted the network cable along 
the 50ft ceiling in the warehouse by climbing to the top of the shelves 
throwing the cable over and through the ceiling struts then back down.

After that, the problem went totally away.

I've got similar stories about another guy who was an old time 
Ham-operator. He under stood gain and signal strength but just could not 
apply it to a computer based model, nor could understand that plugging 8 
radios and two computers into a single 20-amp circuit would cause problems.

Rick Hamell
Tech Blog - http://www.1nova.com/blog
Pacific Northwest Photo Blog - http://www.1nova.com/photoblog

More information about the rescue mailing list