Panasonic Monitor SL90 no green

[G.M. Durrence]

While using my computer I suddenly lost the green color on my
Panasonic SL90 monitor. Can anyone suggest where to start checking,
or does anyone have a schematic for this monitor?

thanks
G.M. Durrence
(To reply remove -nospam)

 

[Newfdog]

While using my computer I suddenly lost the green color on my
Panasonic SL90 monitor. Can anyone suggest where to start checking,
or does anyone have a schematic for this monitor?

thanks
G.M. Durrence
(To reply remove -nospam)

Faulty cable or connector maybe?

 

[Dave D]

Faulty cable or connector maybe?

That's the first thing I'd check.

Dave

 

[G.M. Durrence]

Checked all that, also checked all ribbon cable connectors. Even the
menu doesn't have green so this eliminates cables and connectors. I
also made sure the CRT was socketed well. I suspect an internal CRT
problem but would like to test voltages on the CRT before discarding
it I but need a schematic.

Faulty cable or connector maybe?

G.M. Durrence
(to reply remove -nospam from address)

 

[Newfdog]

Checked all that, also checked all ribbon cable connectors. Even the
menu doesn't have green so this eliminates cables and connectors. I
also made sure the CRT was socketed well. I suspect an internal CRT
problem but would like to test voltages on the CRT before discarding
it I but need a schematic.

change the green drive wire, at the crt socket, with one of the other
colors and see if the green comes up. If it does then the crt is
probably ok.

 

[Dave D]

Checked all that, also checked all ribbon cable connectors. Even the
menu doesn't have green so this eliminates cables and connectors. I
also made sure the CRT was socketed well. I suspect an internal CRT
problem but would like to test voltages on the CRT before discarding
it I but need a schematic.

You don't need a schematic for that. You have three identical video circuits
so comparing voltages, preferably with a grayscale or white display on the
screen at the time, should be straightforward enough. If the green channel
measurements differ significantly from the others, chances are there's a bad
component on the CRT base PCB, ie video amp IC, open resistor, bad driver
transistor etc. It could also be a cracked solder joint, particularly on the
CRT socket. If the R, G and B cathode pins on the CRT are all giving similar
readings, then the green gun on the CRT has probably failed
catastrophically- it happens sometimes.

There's freeware pattern generators on the web which will display
appropriate patterns to help you.

Dave

 

[Tom MacIntyre]

That's the first thing I'd check.

Dave

Green is the closest pin to the left hand side facing, so it could
even be that the cable connector is not screwed in sufficiently.

Tom

 

[Tom MacIntyre]

Checked all that, also checked all ribbon cable connectors. Even the
menu doesn't have green so this eliminates cables and connectors.
??

Tom

I
also made sure the CRT was socketed well. I suspect an internal CRT
problem but would like to test voltages on the CRT before discarding
it I but need a schematic.





G.M. Durrence
(to reply remove -nospam from address)