i have been working with this chassis and cannot figure out what is not working correctly.
back story on the chassis.
chassis was dead on arrival.
capped it re flowed it tested the H.O.T, VR, all the diodes in the hor/virt/power circuit installed a new fly. fired it up with out any problems.
B+ is good at 123v.
but cant figure out what is causing this vertical linearity problem.
i have measured countless resisters and diodes. and changed out all the IC's to eliminate them.
there is a factory mod on the chassis with a resister from the V-size pot to trace with C13 on it negative side. if i remove it it gets smaller but that is all it helps the but vertical linearity problem is still there its just squished more.
the resister is good when tested.
here is some pics and a video of the problem.
the video sucks as my camera is not that great.
video
http://www.youtube.com/watch?v=RKHp919GnJQ&feature=youtu.be
pic 1 is the best it will get with the pot at its minium.
pic 2 is with the pot centerd.
pic 3 is the pot maxed out.
so what would make this happen.
Peace
Buffett
back story on the chassis.
chassis was dead on arrival.
capped it re flowed it tested the H.O.T, VR, all the diodes in the hor/virt/power circuit installed a new fly. fired it up with out any problems.
B+ is good at 123v.
but cant figure out what is causing this vertical linearity problem.
i have measured countless resisters and diodes. and changed out all the IC's to eliminate them.
there is a factory mod on the chassis with a resister from the V-size pot to trace with C13 on it negative side. if i remove it it gets smaller but that is all it helps the but vertical linearity problem is still there its just squished more.
the resister is good when tested.
here is some pics and a video of the problem.
the video sucks as my camera is not that great.
video
http://www.youtube.com/watch?v=RKHp919GnJQ&feature=youtu.be
pic 1 is the best it will get with the pot at its minium.
pic 2 is with the pot centerd.
pic 3 is the pot maxed out.
so what would make this happen.
Peace
Buffett
