KT-2914F Squealing as I turn up brightness

[jconstanza]

I have a KT-2914F that is on a pattern generator, when I have it on an all white screen their is a squealing sound and at the same time their are lines going from left to right across the screen. Also as I turn up the brightness on the flyback the noise gets worse. Cap kit, replaced R206, R207, IC201 & have swapped more than one flyback. Same thing

[grantspain]

the white lines are flyback lines when the screen volts/brightness is too high

some monitors do squeal without a video signal and high brightness-frequency whistle,maybe your pattern generator puts out a signal that the monitor does not like

[jconstanza]

But I have used this generator on other similiar chassis and I have had no problem with it.

[grantspain]

maybe a noisy coil,does any tapping of the chassis affect the noise

[jconstanza]

No not really. I hit it with a screwdriver and nothing.

[grantspain]

i know someone that has a wei ya chassis that does the same,we never got to the bottom of the problem
maybe something to do with the b+ being unstable or set incorrectly but tbh this is one for the experts like rickn,qrz or ken layton

[qrz]

white pic = max beam current = higher load on pwr supply . 
should not have retrace lines on white screen

to set white balance ( video signal must be present )
turn brightness and contrast to min
adjust screen ctl ( on flyback - bottom post) to point that image is just barely visible.
then slowly back off till it disappears .
return brightness and contrast ctls to desired levels

qrz