From: chyang@orpington.engin.umich.edu (Chung Hsiung Yang)
Subject: Re: NANAO 9070U sensitive to power fluctuation
Date: Tue, 17 Nov 92 15:37:16 EST
Organization: University of Michigan Engineering, Ann Arbor
Originator: chyang@orpington.engin.umich.edu


In article <1992Nov16.144523.5222@walter.cray.com>, dpp@cray.com (David Peterschmidt) writes:
> In article Lry@news.cso.uiuc.edu, rg9538@ehsn2.cen.uiuc.edu (Ronald E Garnett) writes:

> >Another problem I've found....curoius as to other peoiples experience...
> >
> >
> >The problem is with my Nanao 9070U monitor.  It usually has a fairly crisp display,
> >but lately I've noticed quite a bit of flicker and wavering of the screen.  At first
> >I though that the monitor was going to monitor heaven, but then I thought to measure 
> >the input power levels.  
> >
> >What I discovered is that the input power to my apartment varies between around 112 V
> >and 120V, depending on what other people have turned on, refrigerators, etc.  This
> >is normal, but the Nanao problem follows the voltage. When the voltage drops much below120 V, the flicering starts.  Around 112 it gets really annoying, as the screen is     wavering as much as an1/8 of an inch.  For a $1000 monitor, this is quite distur> bing!
> >
> >
> >Anyone have any insight or similar experience?
> >
> >
> >
> >Ron Garnett,
> >University of Illinois, Urbana-Champaign
> >
> 
> 
> I've had a similar problem with my monitor (Mitsubishi Diamond Pro
> 17).  The screen bobs up and down occasionally about 1/16 inch and I
> don't know what causes it.  It could well be the same problem you're
> seeing.  If it is the incoming voltage that causes it, I suppose a UPS 
> could be one solution, but I sure don't want to have to buy one.  Is 
> there a cheaper alternative?
> 
> 


	Interesting Problem.  I may be able to offer some answer.

	ONE QUESTION:

	Do you guys live near a radio station, a transmission communication
towar, or a place with a lot of sattilite dishes???

	The power fluctuation really should not affect the monitor performances
because I think the monitor it self should take care of that problem.  
Secondly, the frequency at which the power is operating at 60Hz should not
affect you monitor because the monitor tube is firing electron at a much
higher rate than your power frequency.

	However if there is a strong signal nearby such as a radio station 
or microwave transmission towar or even a tv or video transimission 
dish would conceivably interrupt your video signal because the power line
is able to pick it up quite easily.  (The power line is nothing but a huge
anntenna).

	The way to solve this problem is that 

1.  Check if other residents in your area is having the same problem.  One easy way to check is to usea stereo and rewind a tape or something see if can pick
up radio signal even when you are not tunned in to radio.  

2.  VCR.  IF you get a secondary sound track when you watch a movie there is
interference.  

3.  Call whoever is operating the transmission station and complain.  Since
it is against federal rule to send out such strong signal, they are responsible
for fixing problems like that.  

4.  Get their technician to come out and check out the problem source.  When
identified askethem to install a power line filter.  Or if they can't do it
as them what filter you should buy. (It should be pretty cheap, you can probably
get it in radio shack or some place like that).  


Hope this helps.

- Chung Yang
 

	
> -----------------------------------------------------------------------
> | Dave Peterschmidt        |  Overheard from the mayor of Hiroshima:  |
> | Cray Research, Inc.      |                                          |
> | dpp@cray.com             |       What the f..k was that!            |
> -----------------------------------------------------------------------
> 
> 
>