Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
CIP
 
Posts: n/a
Default Very old monitor repair

Hi everybody,

I got an very old monochrome monitor that is dead.

It's an NEC BU-1201M(E)-1 from about 1985

It had an burnout fuse on the main board, replaced it but the screen remains
black. Audio works. When I switch it on the first second the end of the CTR
lights up but then it gets very dim or even no light at all. I can hear the
HV make a little hunnimg noise.

It's a monitor from a computer that controls a factory. The monitor was
turned on in 1985 and never turned off, but when not in use the screen was
cleared. The video input is NTSC

Checked the power transistors (h/v) and they are ok. Transformer is ok.

Anybody any tips?
  #2   Report Post  
Aidan Grey
 
Posts: n/a
Default

On Wed, 02 Mar 2005 14:15:21 +0100, CIP wrote:

Hi everybody,

I got an very old monochrome monitor that is dead.

It's an NEC BU-1201M(E)-1 from about 1985

It had an burnout fuse on the main board, replaced it but the screen remains
black. Audio works. When I switch it on the first second the end of the CTR
lights up but then it gets very dim or even no light at all. I can hear the
HV make a little hunnimg noise.

It's a monitor from a computer that controls a factory. The monitor was
turned on in 1985 and never turned off, but when not in use the screen was
cleared. The video input is NTSC

Checked the power transistors (h/v) and they are ok. Transformer is ok.

Anybody any tips?


NTSC is standard North American TV video. What you have essentially is a
monochrome
TV being used as a monitor.

You should be able to be able to cheaply buy a replacement TV type monitor.
One
place to check is video security monitors. A security camera being recorded
on a
VCR is using an NTSC signal. The video monitor for such a task would
probably be
a drop in replacement for your defective monitor.

Note that even if you could repair this monitor, it will not be reliable at
its age. A brand
new monitor will give you the reliability needed for a factory environment.


Aidan Grey



  #3   Report Post  
Clint Sharp
 
Posts: n/a
Default

In message , CIP
writes
Hi everybody,

I got an very old monochrome monitor that is dead.

It's an NEC BU-1201M(E)-1 from about 1985

It had an burnout fuse on the main board, replaced it but the screen remains
black. Audio works. When I switch it on the first second the end of the CTR
lights up but then it gets very dim or even no light at all. I can hear the
HV make a little hunnimg noise.

The HV shouldn't hum, it should whistle, you can check for operation of
the flyback transformer by holding a neon screwdriver close to the
transformer, it should glow on a monochrome unit if it's running.

It's a monitor from a computer that controls a factory. The monitor was
turned on in 1985 and never turned off, but when not in use the screen was
cleared. The video input is NTSC

Checked the power transistors (h/v) and they are ok. Transformer is ok.

Anybody any tips?

Replace it, if it's in a factory it's needed! You could probably replace
it with a 12" PAL Unit and get away with it with a couple of minor
tweaks to the frame rate and line sync. http://rswww.com supply chassis
monitors as do many other 'industrial' electronics component suppliers.

--
Clint Sharp
  #4   Report Post  
James Sweet
 
Posts: n/a
Default


"Aidan Grey" wrote in message
k.com...
On Wed, 02 Mar 2005 14:15:21 +0100, CIP wrote:

Hi everybody,

I got an very old monochrome monitor that is dead.

It's an NEC BU-1201M(E)-1 from about 1985

It had an burnout fuse on the main board, replaced it but the screen

remains
black. Audio works. When I switch it on the first second the end of the

CTR
lights up but then it gets very dim or even no light at all. I can hear

the
HV make a little hunnimg noise.

It's a monitor from a computer that controls a factory. The monitor was
turned on in 1985 and never turned off, but when not in use the screen

was
cleared. The video input is NTSC

Checked the power transistors (h/v) and they are ok. Transformer is ok.

Anybody any tips?


NTSC is standard North American TV video. What you have essentially is

a
monochrome
TV being used as a monitor.

You should be able to be able to cheaply buy a replacement TV type

monitor.
One
place to check is video security monitors. A security camera being

recorded
on a
VCR is using an NTSC signal. The video monitor for such a task would
probably be
a drop in replacement for your defective monitor.

Note that even if you could repair this monitor, it will not be reliable

at
its age. A brand
new monitor will give you the reliability needed for a factory

environment.


Aidan Grey




Don't forget that there might be special mounting considerations.

Also I would not nessesarily expect a modern TV to last anywhere near as
long as that monitor did, if the image was still reasonably good I'd repair
it personally.


Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT +1. The time now is 02:39 PM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 DIYbanter.
The comments are property of their posters.
 

About Us

"It's about DIY & home improvement"