NEC FE750 17" PC occasional field collapse

[RJK]

Hello all,

Can anyone help me as to how or where to locate a fault in my NEC FE750
monitor (.25mm dot pitch / flat aperture grille tube). Every few hours,
(it's done it about 5 times now over the past few days), I get loud "Clunk"
sound as if it's just been switched on or off - picture field collapses to a
bright horizontal white/magenta line, (pretty sure it's not white), field
collapse lasts for just a second then "clunk" again, and Windows desktop
appears in the middle of a degauss cycle then it's fine again for hours.

This NEC monitor was in storage from new along with several others for
years, I've had this one for about a year, tube is like new. Shame to have
chuck it for the sake of a disc capacitor ...if that's all that's wrong !!

....any pointers, or referral to a good monitor repair technician
appreciated.

regards, Richard

 

[James Sweet]

Hello all,

Can anyone help me as to how or where to locate a fault in my NEC FE750
monitor (.25mm dot pitch / flat aperture grille tube). Every few hours,
(it's done it about 5 times now over the past few days), I get loud "Clunk"
sound as if it's just been switched on or off - picture field collapses to a
bright horizontal white/magenta line, (pretty sure it's not white), field
collapse lasts for just a second then "clunk" again, and Windows desktop
appears in the middle of a degauss cycle then it's fine again for hours.

This NEC monitor was in storage from new along with several others for
years, I've had this one for about a year, tube is like new. Shame to have
chuck it for the sake of a disc capacitor ...if that's all that's wrong !!

...any pointers, or referral to a good monitor repair technician
appreciated.

regards, Richard

You've probably got a cracked solder joint in there somewhere, perhaps
in the vertical or power supply area. Don't keep using like that or
you'll likely cause further damage.

 

[RJK]

Thanx James,
Perhaps tommorrow I'll whip off the cover and take a look around it with a
bright light and a magnifying glass, if I can't spot anything with the naked
eye.
Tiz all so time consuming ...so many other things to do !

regards, Richard

 

[RJK]

....I whipped off the back and removed the tin shield, blew it out with my
old faithfull electrolux "cylinder" vacuum cleaner - (where you can connect
the hose on a hole at the top to blow - bought it at a boot sale for £5
several years ago....stripped cleaned it and put a tiny drop of oil on each
motor bearing....marvellous for blowing out PC cases . / PSU's etc.)....the
pallaver to get the board out of the thing is a major time consuming joke,
so I reassembled it, I'm going to throw it away if it plays up and get a LCD
monitor from my favourite vendor http://www.aria.co.uk

BTW ...since blowing it out, I haven't had a single field collapse !!
....tracking or arcing via dust ??

regards, Richard

 

[RJK]

....STILL no collapses !!!!

....am pretty sure now that it must have been tracking across dust, there
was some pretty grim black looking powdery dust in there - not excessively
thick, ...very little "household/skin" dust. ...or did I disturb that dry
joint in there, in a beneficial fashion ? !!!

regards, Richard