Hitachi Big Screen picture shake

[RichK]

Hi,

This rear projection unit is about 1 year old. Sorry don't have model handy
with me.

Picture was shrinking a couple of inches on each side, so Sears service was
called, as there's a svc contract with them.

One guy diagnosed a problem and ordered a couple boards, one was the Main
Power Bd, the other sounded like Sych bd.
Another guy replaced the boards.

Picture was fine after the replacement, but now the bottom part of the
picture shakes on all channels. The shaking is intermittent. May go on for
1/2 hr then stop.

Any hints, what may have gone wrong? Clearly there's a new problem, but
when the svc guy comes, it may not be shaking.

Regards,

RichK

 

[Art]

Video tape the sypmtom with a video camera and play it back for the tech.

 

[RichK]

Video tape the sypmtom with a video camera and play it back for the tech.

Done that. Seems to be heat related, as it happens when set warms up.

The parts and service for the visit were over $1000. Lucky there is an
extended warranty.

RichK

 

[Papa_J]

As a service tech, intermittents are almost as nice a problem as a root
canal procedure.
There are service procedures that the techs can perform when they return
short of transferring the set to their shop. It may be prudent to have the
set in operation for an extended period of time so it is acting up when they
arrive.