On Sat, Oct 13, 2018 at 10:38 AM, lop pol wrote:
I'm working on my second 468 and I noticed some horizontal jitter.
On Sat, Oct 13, 2018 at 09:51 AM, Jeff Urban wrote:
In case you haven't, it is important to check if it is a centering problem
or
a triggering problem. Even in auto or free run it is still triggered, so if
it
is the problem could be all the way back at the ramp generator.
If the trace itself is moving and not the sweep (I hope you got that...)
then
I would more look for hash on a PS line somewhere. Of course that applies to
the ramp generator as well but different PS legs of course.
Thanks Jeff.
There is jitter on the A gate out with no input just a free running trace. I
had to put my 465 in 10x to see it but it does match the jitter on the 468.
So... This looks like its going to be a fun one to figure out.
Q181 on the sweep and z axis board was not seated properly. I have no idea how it happened. I have never messed around inside but the base was bent instead of seated. Looking at the schematic I can't tell how that could cause the trace jitter though. The base is connected to ground. So far it seems to be working correctly though. I also installed the EPROMs and images from the Vintage Tek museum. Boards fit correctly and so far so good.
