• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Brightness jumping problem on B&O MS 6000 28" CRT TV

Status
Not open for further replies.

filevans

New Member
Hello all

Please could anyone help me, my ms 6000 has developed an intermittent fault where the brightness keeps going wild and when it goes bright it shows the spaced diagonal horizontal lines a bit lighter than the black background, it is as though someone is playing with the brightness potentiometer on the tube.

I've tried to adjust the potentiometer myself and it doesn't stop it. It is weird as it stopped happening for about a month, and now has started happening again

Thanks to all
 

Jeepdude

New Member
Try adjusting the focus and see if the brightness fluctuates as the focus is adjusted. If that is the case, I would suspect a short in the CRT, focus to screen grid. You can also look to see what is happening to the voltage on the CRT driver transistors. If the B+ is dropping that feeds the collectors, it could be a bad filter cap on that line, usually not intermittent, or a bad solder connection.
 
Status
Not open for further replies.

Latest threads

EE World Online Articles

Loading
Top