Adjusting The Delay-Line Circuit - Philips PM 5508 Operating Manual

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Fig. VII-31. Amplitude error in delay-line
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Fig. VII-32. Phase error in delay-line (notice the deviation of the (B-Y) signal
in respect with Fig. VII-31)
2. Adjusting the delay-line circuit
— Depress push-button "DELAY".
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Adjust the phase and amplitude controls of the delay-line so that
the signal to the red grid is zero, see Fig. VII-30 (upper trace
(R-Y), lower trace (B-Y) ). It may seem that two successive lines on
the scope screen show a different signal level, so that the result
(two TV-lines onto each other) cannot be made zero. This is an
indication of cross-talk between the (B-Y) and (R-Y) channel of the
receiver. In case of incorrect adjustments, oscillograms as shown
in Fig. VII-31 and Fig. VII-32 will be measured (upper trace: (R-Y),
lower trace: (B-Y) ).
Note: The time base speed of the oscillograms is approx. 6.5 µs/division.
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