Hi all, me again;

Here again we have a case where something is acting more strangely than
expected. Set came in bowed top and bottom and vertical lines at the sides were
way off. Ed went ahead and threw in a set of output ICs to no avail. He's
checking the waveforms to the convergence module and the only thing that seemed
strange was the H parabola waveform. Although the DC level was OK, the bottom
was clipped off.

It was then delegated to the dog department (me). Further investigation showed
that the H parabola is not an input, it's an output. After checking as well as
I can I decided to order a waveform IC for it and found it to be NLA, but the
whole module was about $100 so we ordered that. It arrives and as near as I can
tell there is no change. The parabola is now soft clipped, but still not what I
consider right. I got into the convergence setting mode and all controls that
are pertinent to the error work fine. The service mode static proves that the
output ICs are not clipping, the rasters move evenly throughout the screen. You
can't tell this in the customer convergence mode as all you get are the
crosshairs.

It's already been determined that this is not a complete lack of convergence,
top and bottom H lines are converged at the center of the screen. This points
me back to the H parabola, however, as I'm screwing with the controls to see
what's dead and what's alive the set shuts off. I didn't really want to save
changes at this point anyway, but the plot sure thickened. I decided to go to
my other bench and let the thing play undisturbed for a while, come back and go
into the convergence setting mode and it turns of again. This took about
(possibly exactly) the same amount of time to occur as if the sleep timer had
been activated, but does not occur if you just leave it alone.

There is one other thing about this set, it's dark. I've been in the service
menu and the sub pix is working, and video level. The menu is also dark. At
this point I'm starting to think EPROM, but the OSD is displaying the value
from the EPROM right? The value is there, correct and has the proper effect
when adjusted, but it's as if the range is insufficient. Now am I looking at
the micro ?

I don't have a print for the 60601, but the VS XX43,44,45 series uses the same
chipset for the convergence and that is what I'm using. The problem is that
there are two EPROMs and I don't know which one stores the convergence data. I
was also wondering if they come partially preloaded, because I think those DA
values are cabinet/model specific. Looks like your basic run of the mill EPROM,
but if I get one I want it from Mits for that set of course.

Thanx in advance for any help. See the PS below.

JURB

PS: I always try to remember to give TIA because I post this stuff at home and
my ID and stuff is not setup on the shop's PC. I read the replies through
Google and can't post from there. Sometimes I forget, so don't ever think I
don't appreciate your time here. Especially since some of my posts have to do
with TVs from hell.

JURB