GRUNDIG TV CUC 7300 with distorted image

[dxas]

I have a GRUNDIG TV CUC 7300 in which the image is distorted as the drawing below:

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.))))))))))))))))))))))))))))))))
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.))))))))))))))))))))))))))))))))
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This only occurs with the antenna signal (signal from scart does not create distortion) and has a different status on each channel which does not depend on its quality. Could someone help me please to check or replace specific parts?
p.s. I have a picture uploaded at : http://rapidshare.com/files/356836295/100_1753w.JPG.html

[The_AntiRAM]

Change all electrolythic caps on IF DEM / IF AMPL sections - stages.
Also check for dry joints on such stages