Solid State Logic 1266 manual Synchronisation, Sync To Wordclock, Sync To Video Black-And-Burst

Synchronisation

Sync To Wordclock

SRC sync to an external wordclock is indicated by illumination of the ‘WK’ front panel LED. The clock source should be connected to the SYNC IN connector (a BNC socket) on the rear panel. Nominal frequency is 48 kHz 50ppm, and clock pulses should be of 5 V amplitude, positive-going.

Sync To Video Black-And-Burst

The SDI-MADI can also synchronise to a standard (SD) 1 V black-and-burst video signal. The video signal should be connected to the SYNC IN connector on the rear panel. The sync input auto-detects NTSC or PAL standard video.

Sync To AES3

An AES3-compliant digital audio source may be used as the clock reference source. The internal 48 kHz wordclock source is phase-locked to the incoming AES3 signal. Any audio data contained in the AES3 word will be ignored. The audio source should be compliant with AES3-4-2009 Annex D for 75 coaxial transmission and connected to the SYNC IN connector on the rear panel.

Sync To The SDI Inputs

Any of the four SDI inputs may be used to reference the audio outputs. Each two channels of embedded audio in an SDI stream is essentially compatible with an AES3 word format at a sample frequency of 48 kHz and thus this frequency may be extracted and used as the SRC wordclock in the same way as an AES3 sync source. If one or more pairs of audio channels in an SDI signal is carrying Dolby-encoded material, the SRC for that input should be set OFF, and that input should be the sync referenced source.

Use the derived wordclock output as the master sync reference for downstream equipment.

Note: If using this method, it is important to consider how the remaining three SDI sources synchronise in relation to the sync source. If the inputs are asynchronous then they should have their SRCs set to ON. This ensures that the audio content will synchronise to the referenced SDI input.

Note: Passing Dolby-encoded material through sample rate converters will corrupt the Dolby bit stream.

Clock Outputs

A reference clock output is available at the rear panel WK OUT connector in the form of a 48 kHz clock signal, of 5 V amplitude, positive-going, or at the AES OUT connector in the form of an AES3 digital audio signal (“digital silence”). These are derived from whichever synchronisation source is selected.

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