• Blackmagic Design

  hooking decklink up to tektronix box

  Posted by Lexerton on March 1, 2006 at 3:38 pm

  Hi

  The facility I work at has bought a tektronix WVR7000 signal test for QC and mastering.

  I’ve been told by the guys who installed it that the SDI o/p of decklink cards doesn’t go well with the input of the test box.

  I’m no engineer but apperently DL cards SDI o/p doesn’t work with inputs that aren’t re-clocked (Most decks are re-clocked) and the tektronix input isn’t re-clocked. Something to do with front and back porches not lining up.

  Anyone using a DL card with a tektronix WVR7000 without problems? Or am I going to have to buy a Kona card if I want to use the box (it’s pretty sexy for OnLining and quality control.)

  Any BM guys care to comment?

  Ta

  Lex

  Lexerton replied 20 years, 2 months ago 3 Members · 4 Replies
• 4 Replies

• 

  Bob Zelin

  March 1, 2006 at 10:30 pm

  REPLYs below –

  The facility I work at has bought a tektronix WVR7000 signal test for QC and mastering.

  REPLY – the WVR7000 is an excellent scope, similar to the Videotek VTM450 or Leader LV7700 rasterizer scopes, that use a VGA monitor do display the signal.

  I’ve been told by the guys who installed it that the SDI o/p of decklink cards doesn’t go well with the input of the test box.

  REPLY – the guys that have installed it (are they engineers or techs?) are MORONS. The entire purpose of a hi end piece of test equipment is to examine the incomming signal, and determine what is wrong with the input. If you have a clocking error, you should be able to see the output of the Blackmagic Decklink, and observe the poor square wave signal. This is one of the very reasons you buy a scope.

  I’m no engineer but apperently DL cards SDI o/p doesn’t work with inputs that aren’t re-clocked (Most decks are re-clocked) and the tektronix input isn’t re-clocked. Something to do with front and back porches not lining up.

  REPLY – your engineers should assist you with this problem, and show you how to use the scope, and setup the Decklink card for you if necessary. SDI or HD-SDI signals that are run a short distance DO NOT NEED TO BE RECLOCKED. Only SDI signals that are run over 300′ need to be reclocked, becuase the square wave starts to break up. Reclocking cleans up the square wave so the digital input can see this signal correctly. This also becomes an issue if you are using cable that is not rated for SDI or HD-SDI, that cannot handle the bandwidth of SDI or HD-SDI. The short cable out of the Decklink will work PERFECTLY into the WVR7000, but if you must extend your lines, use Belden 1505A, or Belden 1694A. I cannot begin to stress to you that EVEN IF THERE IS A PROBLEM (and there is not) – the Tek WVR7000 will SHOW YOU THE ERROR on the scope ! That’s the point of buying it. The comment “the front and back porches not lining up” is ABSOLUTE NONSENSE. These words are used to describe the horizontal sync interval of a composite analog video signal.
  You are getting a “snow job” from your “technical staff”.

  Anyone using a DL card with a tektronix WVR7000 without problems? Or am I going to have to buy a Kona card if I want to use the box (it’s pretty sexy for OnLining and quality control.)

  REPLY – if you were to purchase an AJA Kona card, you would get the EXACT SAME RESULTS. This applies to any SDI or HD-SDI device. May I suggest, and URGE YOU to bring a digital VTR near the scope (or move the scope to a Digi Beta or HD VTR) and send in a SDI signal into the scope and make sure that the scope is working properly (there are lots of buttons and menu’s on a WVR7000 – just like there are lots of setup menus on a Decklink card – and an AJA card). May I also suggest that you tell your technical staff to get THEIR LAZY GOOD FOR NOTHING ASSES IN THE ROOM WITH YOU AND HELP YOU SET THIS STUFF UP. You are probably an editor, and it is not your responsibility to
  setup new equipment.

  Reclocking – I just love this buzzword stuff.

  Bob Zelin
  Rescue 1, Inc.
  Orlando, FL.
• 

  Bob Zelin

  March 2, 2006 at 4:00 am

  Hi –
  this is the URL to the WVR7000 (7100) – if you scroll down, you will see the
  eye pattern diagnostic to monitor unstable (or unclocked) HD-SDI inputs

  https://www.tek.com/site/ps/0,,24-18752-INTRO_EN,00.html?wt=405&link=/site/ps/0,,24-18752-INTRO_EN,00.html

  Bob Zelin
• 

  Kurt Hennrich

  March 2, 2006 at 8:29 am

  I am running a WVR610A with DL-HD-pro2.
  it works perfect.

  you just have to use correct 75R terminations on the tectronix
  on the input-loop-throughs

  kurt
• 

  Lexerton

  March 2, 2006 at 9:55 am

  Thanks for the replies, guys.

  As always, Bob, your unique manner coupled with your indisputable knowledge is a tonic.

  Although I think a bit of snow storming is forgivable (come on, we all do it from time to time.)

  We had a demo of the scope from the installers (who certainly sounded like engineers) and is a lovely bit of rack candy.

  I’ve seen it on the o/p of a deck and will certainly try the o/p of my dl extreme versus the o/p of the kona LH they have here just to see the difference and hopefully learn something about all this.

  I have to online 13 shows in the next month and want to use the tektronix over the ‘cheap’ EV component analogue scope but at such a critical point I’d rather not be swapping video cards in my machine.

  Looking forward to having a proper geek out with the facilities manager (who, by the way has finally bowed to the demand of FCP for HD online)

  Thanks again for your time.

  Lex

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