CurtPalme.com Home Theater Forum

[md57]

After three years of flawless working, my 9500LC has suddenly lost focus. As you can see it is defocused in some parts of the screen while other parts arts still focused, these have however lost convergence. Strangely when I press keys on the remote the picture changes, e.g. just changeng the brightness one or two steps has other parts of the grid becoming focused/unfocused.

This problem occured a few days ago. Yesterday afternoon while switching on again, everything was o.k. again, a winderfully focused grid, however no convergence. I corrected convergence, everything fine, switched it of -- but in the evening agin the same focus problem.

One more thing, might be totally unrelated: It has stopped sveral months ago to switch to the programmed recall memories. Instaed when pressing the two number recall digits it stayed with a (random?) recall most often one of those that had never been programmed.

Does anyone know what causes these problems?

Any suggestions greatly appreciated

Helmut

[Nashou66]

Looks like it lost the static focus, that controls the upper center and lower focus as where dynamic controls the left and right. Go into the utilites service menu and see what happens to specific RGB zone focus. I have the feeling you'll be able to have control of left and right sides but the three zones top,center and bottom wont have any change. Static is partially controlled by the three MC3408 op amps that are fed a signal from a DAC and from the vertical deflection board.
Unless you have scope its hard to find the bad component. I would try swaping out a FCM first. if its still there then i could be the wave form from either the VDM or CLM.

Athansios

[md57]

Thanks Athansios

within the RGB Focus menu the screen has the same focus problems as I described for the convergence mode. Again, when I change anything like brightness using the remote, the focused / defocused areas of the grid change. There is no way to focus the grid in the Focus RGB menu.

Actually I noticed that the anomality is reproducible with the remote: for example whenever I have the brightness set at 49 the lower right hand portion of the screen is focused, whenever I have the brightness at 51 the upper left hand part of the screen is focused.

Helmut

[Curt Palme]

My guess is CLM issues. It's also possible the HVPS is fluctuating.

[Curt Palme]

My guess is CLM issues. It's also possible the HVPS is fluctuating.

[Nashou66]

Hmmm? I never heard or noticed brightness affecting focus like contrast does. Do this for curiosity, pull the focus conectors off the FCM and do the brightness
adjustment again, I want to see what happens. Brightness is cotroled from the CLm tot he VIM I dont thing it has any components on the FCM. When i had my dynamic focus problem I blew all 9 mosfetts on the FCM . But your is a static focus problem.

I wonder if it is a CLM(contorll Module) problem? So try these two things.

1) Although I dont think its this it wont hurt to try, pull out the clm and press down on all socketed chips.
2) pull the focus conectors off the FCM and see what happens when you adjust brightness, when you pull the focus coil connectors off the fcm you should have an even focus across the screen even if its not focused it should be even.

Athanasios

[Tim in Phoenix]

[Nashou66]