Monitor diagram needed

[Bob]

I have an IBM G70 monitor that has gone dark. It still has high voltage and
the CRT lights. So I think the trouble is in the logic circuitry or the
power supply.

When I switch it on I hear the degaussing surge. But when I press the
degauss button, nothing happens. In fact, none of the controls have any
effect.

Can anyone help? A schematic diagram of this or a similar unit would be of
immense assistance.

Thanks, Bob

 

[Dave]

I have an IBM G70 monitor that has gone dark. It still has high voltage and
the CRT lights. So I think the trouble is in the logic circuitry or the
power supply.

When I switch it on I hear the degaussing surge. But when I press the
degauss button, nothing happens. In fact, none of the controls have any
effect.

Can anyone help? A schematic diagram of this or a similar unit would be of
immense assistance.

Here's a post from Anatek's monitor archive, maybe similar problem:

<QUOTE>
QUESTION NO. P1027-10: IBM 6544-403 monitor has raster but no video.
However, when powering down video is momentarily present. Replaced
LM1205 on CRT pcb-same.

On this G70 model, when there is no video with the signal cable still
attached, but the picture flashes on the screen during shut-off, the
usual cause is a bad rubberized-membrane control panel (under the CRT
face), which must be replaced.
</QUOTE>

Dave

 

[Bob]

Thanks for the quote but my symptoms are different. I simply get NO display
under any circumstances. Not even a flash.

Bob

 

[Dave]

Thanks for the quote but my symptoms are different. I simply get NO display
under any circumstances. Not even a flash.

You could try the diagram for the IBM 6543 (G50), (if you haven't
already), to see if similar enough.

Here's one location:

http://www.geocities.com/monitorss/schematics.html#IBM 6543-G50

Dave
(Uh Oh, time to change SpamMotel email address again - Damn Spammers)

 

[Asimov]

"Bob" bravely wrote to "All" (01 Jul 04 10:22:01)
--- on the heady topic of "Re: Monitor diagram needed"

Bo> From: "Bob" <[email protected]>

Bo> Thanks for the quote but my symptoms are different. I simply get NO
Bo> display under any circumstances. Not even a flash.

Try turning the screen control on the fbk. I've seen one with a bad
spot on this type before. Be very, very careful of High Voltage!

A*s*i*m*o*v

.... You mean 15" sparks are SUPPOSED to come out of this thing?!?

 

[Bob]

Thanks Dave but that link doesn't work.

Any other ideas?

Bob

 

[Dave]

Thanks Dave but that link doesn't work.

Any other ideas?

Try:

http://fileshare.eshop.bg/

Also, just do a Google search:

http://www.google.com/search?q=ibm+g50+schematic

Dave