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Published Tips - General Tips
Written by Administrator   
Tuesday, 04 November 2008 22:34

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Disclaimer


The procedures described in this document require access to potentially dangerous voltages, proximity to the CRT and its implosion risk, and other possible dangers lurking inside a television set. We will not be responsible for personal injury resulting from attempting these repairs nor damage to the equipment that may result from lack of soldering experience or inadequate de-soldering or soldering equipment.


Please read this guide completely at least once before you attempt to fix your TV. You may also want to print the document out. To do so click the "print" icon at the top of this article.  





First Fix

One or all tubes are not staying on.

Symptoms....

TV Tubes are coming on then shutting down within a matter of seconds or minutes.

Cause:  In some cases the tubes brightness is off balance and when the TV detects this it will shut down to protect the tubes. The procedure below outlines how to turn the brightness knobs "Screen" all the way down then back up one by one. The goal here is to see if you can keep the TV on. If however it does the same exact thing as before the below test you may have another issue.


   Unplug Power



Unplug the power from the wall! 



 

Locate whats called the Focus Block. In the photo below its the black box with the "6" knobs. 

On your TV if may look different of have colored knobs.  On some models is also hidden behind a flap on the front panel.


 


Once you locate the focus block mark the current positions of each knob with a marker. 

This is important since we will want to adjust it back to its original settings if it does not fix the issue. 


Once you have marked the original locations find the ones marked "Screen" on the focus block. There should be three of them. One for each color tube. 

Turn each one all the way down - counter clockwise.  This turn down the brightness of each tube just like a dimmer switch.


With all three turned down power on the TV. 

Slowly turn up just one "Screen" knob. Example - pick the one for the blue tube and turn it up slowly. 

The goal is to get the tube to come on and shine up on the screen and for it to stay on.  

Note that if you turn any tube up too much the TV will shut off again. This is normal.  If it does this start back over at Step 1. 

If you get the first tube to stay on without the TV shutting off move on to the second tube, then the third.

Basically your goal here is to adjust the brightness levels of all three tubes to a point where the tv no longer shuts down. 

If however doing the above does not help - readjust the knobs back to where they were. 





Second Fix 

TV has faint vertical or horizontal lines showing up on the screen

Symptoms....

TV Tubes are on but there are faint lines on the screen.

Cause:  In some cases the tubes brightness is too high or the tube is going bad. Adjusting it down just a bit may help


  

Power the TV on....


Locate whats called the Focus Block. In the photo below its the black box with the "6" knobs.

On your TV if may look different of have colored knobs.  On some models is also hidden behind a flap on the front panel.



Once you locate the focus block mark the current positions of each knob with a marker.

This is important since we will want to adjust it back to its original settings if it does not fix the issue.


Cover each tube up with paper plates so that only one color shines up at the same time. See if you can determine which color has the faint lines in it. Note that its not common to have it in more than one tube. If so the brightness is not the issue. 


Once you narrow down which tube has the issue slowly turn down the "Screen" knob for that color until the faint lines go away. If it does not help this may not be the solution. In that case readjust the knob back where it was originally. 




We value your feedback. Please let us know if the above kit and instuctions helped resolve your TV problem. Also, any feedback on how we can improve our kits, instuctions, or website is always appreciated.







Last Updated on Friday, 13 December 2013 15:37