Re: Lisa

[Rubywand <rubywand@swbell.net>]

Snit writes ...
> 
> I am the proud owner of a Lisa now.  I know this is an Apple II group,
> but hey, you're all I've got.  A friend gave it to me, telling me it
> had not been turned on for years.  We plugged her in, and she worked
> like a charm.  Accept the screen was jumping around.  After a few
> hours of play, the screen became a horizontal line in the center of
> the screen.   Eeek!  Is Lisa dead?  Poor girl.  Any ideas what I
> should do? ....


     Lisa is, probably, fine; but, her monitor may be in trouble.

     Does Lisa have any external connector to the monitor? If there is 
one, try unplugging and re-plugging. And/or try wiggling it.
 

     From the "jumping around" symptom, it sounds like some control 
potentiometer-- like the one for Vertical Size-- was making poor contact. 
This could have led to burning of the pot's carbon resistance element and 
loss of vertical output.

     With the monitor OFF, you could try squirting Radio Shack TV Control 
Cleaner into each  control (it needs to get inside the pot) and wiggling 
each control. (If a control feels really scratchy or crunchy, it is a 
good candidate to be the one that's messed up.) This may restore your 
display. Eventually, you may need to have the control replaced.

     If all of the controls you can reach seem to be okay, the problem 
may be rougher to fix. Other, less happy, possibilities include a burned 
internal setting control, a blown capacitor and/or a blown Vertical 
output transistor, ... .

     Anyway, try the control Clean & Wiggle approach. Lots of times it 
works.   


Rubywand