I hadn't thought of that. I hope that's not it. :(
Bill.
:-)(((
On Jun 29, 2014, at 5:00 PM, Jason Perkins <perkins.jason_at_email.domain.hidden> wrote:
Watching some of the guys who restore vintage TVs I've seen these sort of odd problems from bad flyback transformers as well :( I'd check the PSU first though since that's much easier to fix.
-J
On Sat, Jun 28, 2014 at 10:56 PM, Bill Vogel <hightrailrider_at_email.domain.hidden> wrote:
I'm thinking that there is a problem in the horizontal blanking circuitry, the link that goes from the
flyback transformer to the video. (R16, CR4, etc.) Maybe an open cap is allowing the blanking
signal to 'ring'? If you have an oscilloscope it would be useful to look at the signal in that area.
Hope that is helpful.
Bill.
:-)(((
On Jun 28, 2014, at 5:12 PM, James MacPhail <gg__at_email.domain.hidden> wrote:
Examples of Ken's Lisa symptoms are here:
http://members.shaw.ca/sigmaseven/boylephoto1.JPG
http://members.shaw.ca/sigmaseven/boylephoto4.JPG
The symptom is the wide dark vertical bars at the left third of the screen (ignore the gibberish image in the second picture).
I suspect the problem is related to the +28V supply on the video board, but perhaps someone knows more specifically what part needs to be changed?
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Received on 2015-07-16 08:00:03
