Adjusting the Sync and Subcarrier Phases

When using two or more players, as in an A/B roll editing system, it is necessary to synchronize the sync and subcarrier (for composite signals) phases of the signals to be edited. If they are not synchronized, picture instabilities or color break-up may occur at edit points.

After configuring the editing system, use a vectorscope to adjust the sync and subcarrier phases of the recorder and players. Subcarrier phase adjustment is necessary when using composite signals and Y/C signals.

This unit (player 1)

Switcher (DFS-700A/700AP) a)

DSR-1500A/1500AP (recorder)

UVW-1600/1600P (player 2)

75 Ω coaxial cable (A) b)

75 Ω coaxial cable (B) b)

Vectorscope (Sony Tektronix 1750/1751, etc.)

PVE-500 Editing Control Unit

a)The sync and subcarrier phases of the output signal from the DFS-700A/700AP switcher are automatically adjusted.

b)Ensure that the 75 Ω coaxial cables (A) and (B) (not supplied) are of the same length.

Performing a phase adjustment operation

1 Press the SCH button on the vectorscope. The vectorscope switches to SCH mode.

2 Press the B channel button on the vectorscope.

This displays the black burst signal from the switcher.

3 Press the EXT button on the vectorscope.

This switches the vectorscope to external synchronization mode.

4 Adjust the phase synchronization control on the vectorscope so that the sync and subcarrier phases are close to the reference line.

92 Adjusting the Sync and Subcarrier Phases