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Re: Technical question for the Pros using yesterdays gear with todays (long)

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Hi Keith,
I again thank you for a voluminous and educational reply. I vaguely remembered the reasons for the mastering delay, and appreciate your detailed explainations very much. The DBX 700's do have external BNC type 'input' & 'output' jacks labeled 'SYNC' on the rear panels. The manual states: 'These are used for broadcastiing and recording applications where the 700 must be synchronous with video sources coming either before or after it (e.g., satellite transmission and multiple-700 applications). If a standard video-synchronization signal is the input-it must be 4-v, negative-going, and ac-coupled as well -- then the 700 will generate video in synch with it. In other words, the time rate of the 700 adjusts to that of the source, with the Sync output a buffered version of the input. If there is no such input, the ouput is at the 700's free-running rate (within 0.1 percent of the NTSC standard)'.

However, the Addendum to the maunal states: 'Model 700s without our dealer-installed Copying-function modification require a synch signal that is negative-going, dc-couple (not ac-coupled, as the text says), and with levels that are 4 v and ground. (8v peak-to-peak loaded by 75 ohms, as is the case here, drops to 4 v.) These units have serial numbers below 794 (with the exception of no.774). If your particular unit is in this group, you can have your dealer perform the Copy modification. Units no.794 and above, as well as pre-794 unis that have received the dealer Copy modification, accept the industry-standard ac-coupled synch inputs'.

Unfortunately, two of my four units are below this serial number, and two units are above, without any indication if the earier units have received this modification, and I don't want to damage something without determining this first.

The main point here is that the 700s do have the SYNC clock capability, this is good news, if I can lock the clocks to a PC and then as you have indicated strip/rip the data to a hard drive / burner, then I might have something niffty to archive with. However I'm not there yet..;)
Keith, I've been racking my brain all day trying to understand paragraph seven of your post though...'Now back to the DBX units'.
It seems as though your saying here that I would need to record video to a VCR/VTR unit then decode to a second decoder to send the raw digital signal to the PC. If the digital signal, Encode & Decode are available at the port, without the NTSC video format process applied, would this not be the signal to 'Burn' to a disc? I understand that the 700s are not simultaneous Encoders/Decoders, but with four units, I was hoping that utilizing the port to a PC, that I might be able to have 8 channels one way or 4 channels simultanously. I think that I've miss understood what your saying, the signal flow you were discribing, can you please give a flow chart description?

I do know a computer geek that just might have an idea of how to record the raw data, I'll give him a call. And of course I'll let you know what results I get. If you think a pdf file of the manual would help I could post on a web page for your viewing as well. Thanks again for your input on the 'MAD' idea....;)

Rick


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