Re: Screen Stabality Fix

Yes whatever is shown on the right has a big effect on this "issue".

I did some more tweaking and found that if I decrease the width some the picture gets brighter. My system has always had an issue where black areas on the screen would change the overall brightness of the screen. For example when you open Preferences and it draws the black box the entire screen gets darker. Adjusting the width control to near minimum makes the brightness stable.

I suppose I need to break out my scope and check some things on the video board.

-J

On Sun, Mar 16, 2014 at 7:04 PM, Tom Stepleton <stepleton_at_email.domain.hidden> wrote:

> Yeah, I've seen this on my Lisas for a while but haven't ever done
> anything about it. IIRC, the degree to which this persists varies depending
> on what is being shown on the right side of the screen. It would be
> interesting to know whether this happens for you, too. Try opening a window
> and having it overlap most of the right side of the screen. For me, this
> modulates the misalignment effect.
>
> --Tom
>
>
> On Sunday, March 16, 2014 2:45:37 PM UTC-4, compu_85 wrote:
>>
>> So I'm going to bump this old thread up. I never got the wiggle issue
>> completely sorted out, but as time went on my system developed another
>> interesting issue: Sometimes the scan lines don't line up. It can be made
>> better by adjusting the horizontal phase, but as the system warms up it
>> will get worse, and it is also affected by what is displayed on the screen.
>>
>> Here's a video I made showing the problem: https://www.youtube.
>> com/watch?v=MBSTgL1Hj74
>>
>> Any suggestions? IIRC I replaced the caps in the PSU back in 2005 but now
>> I can't recall exactly if I did all of them or just the main filters.
>>
>> Thanks!
>>
>> -J
>>
>> On Sunday, May 14, 2006 5:53:25 PM UTC-4, compu_85 wrote:
>>>
>>> Sorry to start a new thread on this, but it wouldn't let me bump the
>>> old one.
>>>
>>> "Withthe phase control adjusted to the extreme, the addition of a
>>> capacitor between the base of Q8 and ground will move the image back
>>> towards the center of the screen. (The left side of R54 is
>>> equivalent to the base of Q8. The bottom of C5 and the emitter of Q8
>>> are ground.) The amount of capacitance required will depend on the
>>> particular machine. 0.02uF (0.02 micro-Farads) is a good starting
>>> point. "
>>>
>>> I have done this, and a .02 and .01 uF cap put the screen at a nice
>>> alignment. The only problem is that now the whole screen shakes a lot
>>> when the hard disk power is plugged in (this is a 2/10 with a 1.8A
>>> unit). Does this indicate my power supply is weak?
>>>
>>> -Jason
>>>
>>> --
> --
> -----
> You received this message because you are a member of the LisaList group.
> The group FAQ is at http://lowendmac.com/lists/lisa.html
> To post to this group, send email to lisalist_at_email.domain.hidden
> To leave this group, send email to lisalist+unsubscribe_at_email.domain.hidden
> For more options, visit this group at
> http://groups.google.com/group/lisalist
> ---
> You received this message because you are subscribed to the Google Groups
> "LisaList" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to lisalist+unsubscribe_at_googlegroups.com.
> For more options, visit https://groups.google.com/d/optout.
>

-- 
Jason Perkins
313 355 0085

-- 
-- 
-----
You received this message because you are a member of the LisaList group.
The group FAQ is at http://lowendmac.com/lists/lisa.html
To post to this group, send email to lisalist_at_email.domain.hidden
To leave this group, send email to lisalist+unsubscribe_at_email.domain.hidden
For more options, visit this group at http://groups.google.com/group/lisalist
--- 
You received this message because you are subscribed to the Google Groups "LisaList" group.
To unsubscribe from this group and stop receiving emails from it, send an email to lisalist+unsubscribe_at_googlegroups.com.
For more options, visit https://groups.google.com/d/optout.



text/html attachment: alternate version of message