Occasionally when demonstrating PTE at clubs and seminars one of two problems have been known to occasionally occur:lines appear on the projected picture when an animation is taking place but these do not show on the laptop screen.
the sound track is affected by the addition of noise generated by the computer circuits.
Either of these faults can be immediately cured by running the laptop on the battery and so the switched mode power supply is the suspect.
Has anyone else encountered this problem and more importantly have you discovered a cure!!!
I didn't find the right solution from the Internet.
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