Sync HD Video Reference Problem

[jkatcher]

Hey all -

I am feeding SD black burst into the "video ref in" on the back of the Sync HD and then putting the terminating cap on the "video ref out". When I select "Video Ref SD" as my clock reference in the session setup, it is unable to lock. Am I missing something really basic?

The Sync HD is connected to the 192 through the loop sync, and the Sync interally locks to itself on Internal / VSO.

Thanks so much for any help...

[Bob Brown]

Are you sure you are selecting the proper reference format in Pro Tools (NTSC or PAL)?

Does the lock light on the SYNC HD front panel go solid?

[jkatcher]

Hey bob -

Yes, I am selecting NTSC, but the lock light on the front of the Sync just continues to blink...

[the dude]

A few reasons that it won't lock to Black
1.) signal to high ( strong )
2.) signal to low
3.) ground loop on the sync line
4.) wrong signal

Now for the solution for each

1.) place a BNC "t" at the input with a 75 ohm term on the "t"
So the sync and a term. Go on the input at the input
And not at the output/trough bnc
2.) run the signal through a terminated video DA
3.) try the singal on any monitor and see if there is a hum bar displayed
4.) same as #3 except see if the video monitor will sync also

This signal on a video monitor should be a clean black screen

Is the sync IO locked but not resolved or won't even lock?

[jkatcher]

Now I've actually got a bigger problem, which is much more pertinent since I have a session tomorrow. My sessions are all playing back at a slow, inaccurate speed. I work almost exclusively at 48k and the 192, Sync and session are all in agreement about the sampling rate. I've detached the video reference completely and just have the Sync HD looped to the 192 and back.

I'm choosing Internal/VSO as the reference, and though it locks, it continues to play back at the wrong speed. Only when I select 'loop sync', does it play back correctly but then is no longer locked. Really appreciate any advice....

[Chief Technician]

Do you have the loop sync out of the SYNC|HD connected to the loop sync in of the 192 I/O? Do you have the loop sync out of the 192 I/O connected to the loop sync in of the SYNC|HD?

If you open the session setup window, the clock source should be set to SYNC. If you tab open the Sync Setup section of the window, and choose the SYNC clock reference as Internal/VSO, does that result in both interfaces being locked and the audio playing back at the proper speed?

[jkatcher]

It turns out that my Sync HD was systematically shutting down and is now off for repair at Digidesign. Thanks for all of your help!