Question about SAMTRON 78DF 17" CRT Monitor

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Monitor's "Control Lock/Unlocked" menu appears by itself

My SAMTRON 78DF monitor is having a problem. The Monitor's menu appears by itself. It was discussed in a previous description but not resolved. It shows the control lock window and will fluctuate between locked and unlocked without activation of the menu button on the monitor itself. The control lock window is switching between the CONTROL LOCK and UNLOCKED mode every each 5 seconds and is smack in the middle of the screen. When unlocked I can press the exit button and it will change to the blue - access function window but the up down buttons do not work. It will then go back to the red locked window and continue through the rotation. Please advise...

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Re: Monitor's "Control Lock/Unlocked" menu appears by...

I have a PDF of the service manual, and I'll be glad to email to you upon request. It may help.

Posted on May 30, 2007

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Re: Monitor's "Control Lock/Unlocked" menu appears by...

Press four buttons simultaneusly
and keep presed for
10 seconds or upto unlocked message
will apaear

Posted on Oct 07, 2011

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