If the photograph is clicked, it grows.

Video signals containing a 60 Hz ripple or a DC offset make it difficult to view the video signal with an oscilloscope. The Video Display Clamp provides a stable signal to the oscilloscope by clamping the back porch of the video signal to ground reference. This does not affect the signal source. NTSC PAL HDTV (component and composite) CLAMP FILTER. When ON, the Video Display Clamp ignores the presence of a color burst signal. This helps ensure a ground level for the back porch. The filter does not remove the color burst signal from the video waveform. SYNC POLARITY. Select + to match sync pulses having a positive leading edge. Select -- to match sync pulses having a negative leading edge.