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weevie833
Reference question
on Nov 12, 2007 at 12:17:25 am

Just migrated a K2/G5 DP [2003] edit station from one room to another. Everything the same except that the Reference In CV cable is about 50ft long versus about 8ft before, running from BB box to card.

Having some stability problems with Control Panel set to Ref In. Goes away set to Freerun. Happens regardless of the format/frame rate.

I've tried two cables -- one I crimped myself as a single line, the other using existing cables, two, with a barrel about midway. Same results.

Did the usual stuff -- repair permissions, cache cleaner.

Any chance my black burst box is too weak [if there is such a thing?]. What are the chances of two sets of bad cables? No significant interference that I can determine, such as passing major electrical stuff or wireless transmitters. Am I stretching the distance limits for this kind of thing? I am running the BB connection directly without a video DA in between either. Tried different ports on the BB as well.

Thx - Steve


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Bob Zelin
Re: Reference question
on Nov 12, 2007 at 1:37:32 am

Hi Steve -
black burst is an analog video signal. You can use the cheapest piece of crap video cable, and run it 1000', and you still won't have any problems. HOWEVER, there are black generators, like the Horita BSG-50 that MUST be terminated with a 75 ohm BNC terminator (or switch on the VTR) to work. If you put a Horita BSG-50 into a K3 box that has a reference loop (with no auto termination), the Horita BSG-50 will do NOTHING. In addition, the Horita BG-50 (not BSG-50) is NOT a black generator, and will never work in this application.

Could you have made 2 bad cables - anything is possible, and you can test this out RIGHT NOW. Take one of the BNC cables and put composite video out from your VTR into your TV monitor composite video in. Do you see a picture? Then the cable is working. NEVER asssume a cable is good.

If your signal is terminated, and your black generator is good, and your cable is good, the last resort - before ordering another Kona board - is to DRAG your VTR into your edit room, and use your working "short" cable, and see if it starts to work. No one here (at least not me) is saying that the Kona card is infalible - it certainly can be broken, but you should try the other things first.

Bob Zelin


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weevie833
Re: Reference question
on Nov 12, 2007 at 1:54:16 am

Thx Bob -

Little clarification: I made the first cable, but the second [two cables + barrel] were existing, manufactured cables that I had used with my Avid [now defunct]. In addition, I used a cable tester for all the lines I ran that day and got solid green on all of them, and none of the others have been a problem.

I will have to check the model of BB gen, but it has been the mainstay of our machine room since day one without a problem. Second, we are talking about a K2, with no reference loop out. Even so, we used the same reference gen for the AJA IO [which has a ref loop] without termination on the IO loop out, without a problem.

The thing that is perplexing is that it sometimes worked after I installed it. So I attributed it the instability to the tendency for the system to be switched from SD to 720 with enough frequency to make FCP act sketchy requiring a cache purge. But the more recent reports indicate that the problem had become pervasive, so I told them to switch to Freerun, and set the DBeta to Video In for outputting to tape [which this workstation is not primarily intended to be used for].

BTW, the MaxxPro RAID is working great, even with its Frankenstien-ish PCI-X setup. Flawless. Exactly what I needed it to do. thx for your help.

Steve


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