Mitsubishi vs-582rs focus problems

[Mike]

This is the same set i had trouble with on the vertical.

I have the vertical section and convergence completely restored, and it
displays a good picture.

The problem, is really poor focus.

This doesnt have your traditional electrostatic focus circuit, that has a
wire running to the back of the CRT with its own seperated pin.

It i believe, i may be wrong, but has electromagnetic focus. There is a
circuit somewhere that takes care of the focus.

I heard in the grapevine, bad solder around T502, and i also heard R8000
areas or something.

Anyway, I just went through the whole entire deflection board and redid all
solder. the focus improved a weeee bit. i also noticed, that if you look
closely to words you can see a slight 1% in and out of focus flicker. but
barely noticable. So i suspect there is bad solder somewhere

Where is the focus circuit and controls? where is R8000?

the deflection board has to be working fine.

 

[Mike]

P.S. if i turn the contrast all the way down, and the brightness near all
the way down, the focus is perfect, but the picture is somewhat invisible.



"Mike" <temp@temp.com> wrote in message
news:_vFNb.9422$f97.3933@fe3.columbus.rr.com...

This is the same set i had trouble with on the vertical.

I have the vertical section and convergence completely restored, and it
displays a good picture.

The problem, is really poor focus.

This doesnt have your traditional electrostatic focus circuit, that has a
wire running to the back of the CRT with its own seperated pin.

It i believe, i may be wrong, but has electromagnetic focus. There is a
circuit somewhere that takes care of the focus.

I heard in the grapevine, bad solder around T502, and i also heard R8000
areas or something.

Anyway, I just went through the whole entire deflection board and redid
all
solder. the focus improved a weeee bit. i also noticed, that if you look
closely to words you can see a slight 1% in and out of focus flicker. but
barely noticable. So i suspect there is bad solder somewhere

Where is the focus circuit and controls? where is R8000?

the deflection board has to be working fine.

 

[Mike]

i didnt bother to look at convergence board, and i about died with what i
saw. tons of bad joints.


resoldered it all, and bingo perfect focus. i fine tuned it abit.


"Mike" <temp@temp.com> wrote in message
news:_vFNb.9422$f97.3933@fe3.columbus.rr.com...

This is the same set i had trouble with on the vertical.

I have the vertical section and convergence completely restored, and it
displays a good picture.

The problem, is really poor focus.

This doesnt have your traditional electrostatic focus circuit, that has a
wire running to the back of the CRT with its own seperated pin.

It i believe, i may be wrong, but has electromagnetic focus. There is a
circuit somewhere that takes care of the focus.

I heard in the grapevine, bad solder around T502, and i also heard R8000
areas or something.

Anyway, I just went through the whole entire deflection board and redid
all
solder. the focus improved a weeee bit. i also noticed, that if you look
closely to words you can see a slight 1% in and out of focus flicker. but
barely noticable. So i suspect there is bad solder somewhere

Where is the focus circuit and controls? where is R8000?

the deflection board has to be working fine.

 

[Mike]

AAAAAAAHHHHHHHHHHHHHHHH

IVE FUCKING HAD IT.

Someone help.

The focus problem is driving me nuts. The convergence is perfect, but yet
its part of that board.

I can get the focus just perfect, and it will pop in and out like crazy.
exactly like a bad solder joint. BUT ITS NOT I resoldered every fucking
thing on that board, including a bad eyelet on the -12v regulator.

I also used a can of tv tuner cleaner to clean the focus pots, but it didnt
help.

the focus wont stop going in and out no matter what i do. All solder has
been redone, on both the convergence and deflection boards. someone know the
source of this problem? or even how this focus circuit works? its no where
near like the conventional circuit from the flyback, this isnt a flyback
derived focus circuit. it uses its own STK pack for the focus i believe. It
was working just fine yesterday, and it started going rancid on me again.

AAHH.

someone help please








"Mike" <temp@temp.com> wrote in message
news:_vFNb.9422$f97.3933@fe3.columbus.rr.com...

This is the same set i had trouble with on the vertical.

I have the vertical section and convergence completely restored, and it
displays a good picture.

The problem, is really poor focus.

This doesnt have your traditional electrostatic focus circuit, that has a
wire running to the back of the CRT with its own seperated pin.

It i believe, i may be wrong, but has electromagnetic focus. There is a
circuit somewhere that takes care of the focus.

I heard in the grapevine, bad solder around T502, and i also heard R8000
areas or something.

Anyway, I just went through the whole entire deflection board and redid
all
solder. the focus improved a weeee bit. i also noticed, that if you look
closely to words you can see a slight 1% in and out of focus flicker. but
barely noticable. So i suspect there is bad solder somewhere

Where is the focus circuit and controls? where is R8000?

the deflection board has to be working fine.

 

[BWL]

I've never seen the focus IC do that, but it's certainly possible, as I've seen
dozens of the convergence IC's with bad internal connections being very
intermittant.