HD-SDI signal dropped. What caused that? at DVinfo.net

Go Back   DV Info Net > The Tools of DV and HD Production > External Video Recording Solutions > Convergent Design Odyssey

Convergent Design Odyssey
...and other Convergent Design products.


Reply
 
Thread Tools Search this Thread
Old July 17th, 2009, 03:50 AM   #1
Major Player
 
Join Date: Oct 2006
Location: York, UK.
Posts: 224
HD-SDI signal dropped. What caused that?

While filming some interviews yesterday, my XDR seemed to lose the SDI signal a couple of times (fortunately not while filming). Aside from a cable problem, what may have caused that?
Justin Benn is offline   Reply With Quote
Old July 17th, 2009, 08:07 AM   #2
Inner Circle
 
Join Date: Dec 2002
Location: Augusta Georgia
Posts: 5,413
Dear Justin,

1. I would, using the same cable, hook it up to a monitor. Do you lose the image on the monitor? Was there any power problems.

If possible test with another source.

2. Are the BNC connectors on the camera and Flash XDR good? Examine the inside connector and check that it looks good. Compare it to another BNC connector. Use a high powered maginfying glass, or a camera in macro mode.

3. The first thing to check is the cable. Are you using high-quality, true 75 Ohm, HD-SDI cables? 50 Ohm cables and connectors are not appropriate.

4. What camera were you using? Is the HD-SDI signal from the camera typically stable.
__________________
Dan Keaton
Augusta Georgia
Dan Keaton is offline   Reply With Quote
Old July 17th, 2009, 09:13 AM   #3
Major Player
 
Join Date: Oct 2006
Location: York, UK.
Posts: 224
Trouble-shooting.

Hi Dan,

Yes - a round of quick trouble-shooting is in order. Just wondered if there were any firmware issues - sorry to impugn such a thing! I'm hoping it's the cable, although it's supposed to be a true 75 ohm item.

Camera is an EX3. Normally the signal is perfectly stable.
Justin Benn is offline   Reply With Quote
Old July 17th, 2009, 09:17 AM   #4
Inner Circle
 
Join Date: Dec 2002
Location: Augusta Georgia
Posts: 5,413
Dear Justin,

No offense taken at all.

I do not know of any firmware issues that would cause the Flash XDR to lose sync with your input.
__________________
Dan Keaton
Augusta Georgia
Dan Keaton is offline   Reply With Quote
Old July 22nd, 2009, 07:53 AM   #5
Major Player
 
Join Date: Oct 2006
Location: York, UK.
Posts: 224
Phone

I wonder if it may be the firmware? It was perfectly fine before I installed the last update. Perhaps I should call you.
Justin Benn is offline   Reply With Quote
Old July 22nd, 2009, 08:00 AM   #6
Inner Circle
 
Join Date: Dec 2002
Location: Augusta Georgia
Posts: 5,413
Dear Justin,

I am assuming that you are using our latest firmware 1.0.141.

I do not know of any reported problems with 1.0.141, but I will check with Tommy.

If you send me a private email, I will respond with all of my phone numbers.

Also, you can always go back to a previous version of the firmware and see if the problem goes away. This would be a great test.

To go back to a previous version, just use the same procedure as you use to install the latest firmware, just use an older version.
__________________
Dan Keaton
Augusta Georgia
Dan Keaton is offline   Reply With Quote
Old July 28th, 2009, 12:39 PM   #7
Major Player
 
Join Date: Oct 2006
Location: York, UK.
Posts: 224
Champion

For anyone who has followed this thread, it seems that my early XDR unit may be the culprit.

BUT - Convergent Design helped me diagnose the issue with same day replies (from half a world away) and offered to replace the unit with a recent build and keep me shooting.

I like these guys.

J.
Justin Benn is offline   Reply With Quote
Old July 28th, 2009, 12:57 PM   #8
Inner Circle
 
Join Date: Dec 2002
Location: Augusta Georgia
Posts: 5,413
Dear Justin,

We really appreciate your kind post.

We do our best to support our customers.

In most of my emails, I indicate that I try to be available 24/7 and I provide all of my phone numbers. When I am traveling I am sometimes unavailable.

I just feel that filmmaking and many other audio/video work is not a weekday, 9 to 5 type job. When you are on set and need an answer, most people need it right now. We are here to help.
__________________
Dan Keaton
Augusta Georgia
Dan Keaton is offline   Reply With Quote
Old July 30th, 2009, 07:45 PM   #9
Major Player
 
Join Date: Nov 2002
Location: Tokyo
Posts: 898
BNC connectors ...

Quote:
Originally Posted by Justin Benn View Post
While filming some interviews yesterday, my XDR seemed to lose the SDI signal a couple of times (fortunately not while filming). Aside from a cable problem, what may have caused that?
BNC connectors are 50 Ohm and 75 Ohm. Which ones are you using?
Dean Harrington is offline   Reply With Quote
Old July 30th, 2009, 08:57 PM   #10
Inner Circle
 
Join Date: Dec 2002
Location: Augusta Georgia
Posts: 5,413
Dear Dean,

Just so everyone understands, all HD-SDI cables should be made with 75 Ohm cable with 75 Ohm BNC connectors.
__________________
Dan Keaton
Augusta Georgia
Dan Keaton is offline   Reply With Quote
Old July 30th, 2009, 09:05 PM   #11
Major Player
 
Join Date: Nov 2002
Location: Tokyo
Posts: 898
good idea to stipulate ...

Quote:
Originally Posted by Dan Keaton View Post
Dear Dean,

Just so everyone understands, all HD-SDI cables should be made with 75 Ohm cable with 75 Ohm BNC connectors.
I didn't know this about the BNC connectors ... cables yes but BNC connectors no until I checked.
Dean Harrington is offline   Reply With Quote
Old July 31st, 2009, 04:22 AM   #12
Major Player
 
Join Date: Oct 2006
Location: York, UK.
Posts: 224
Canare

75 Ohms - at least it said so on the labeling.
Justin Benn is offline   Reply With Quote
Old July 31st, 2009, 05:35 AM   #13
Inner Circle
 
Join Date: Dec 2002
Location: Augusta Georgia
Posts: 5,413
Dear Justin,

What is the part number of the Canare cable you are using? This should be printed on the cable.

When we build cables, we use LV61s, which is very flexible, for short cable lengths,
and L-4CFB for longer runs (over 10 feet, which is less flexible).

L-5CFB could be used for very long runs.

There are other Canare cables that can be used successfully.

Of course, outside the Canare line, there are other cables that work.
__________________
Dan Keaton
Augusta Georgia
Dan Keaton is offline   Reply With Quote
Old July 31st, 2009, 08:06 AM   #14
Regular Crew
 
Join Date: Sep 2008
Location: Jacksonville, VT USA
Posts: 100
For very short runs, like 10 feet, you can use almost anything to move HD-SDI (and I mean ANYTHING, try 2 coat hangers for example, well maybe not coat hangers...). We routinely move HD-SDI on BNC's up to 250 feet. Most the interconnects between TV trucks on NASCAR for example are BNC's. Most of the runs are 100-250 feet.

Most of the wire I see in the field is made by Belden and I would recommend 1855A which is a very nice flexible coax rated up to 260 feet and is only about 1/8" in diameter. There is other coax available for distances up to 500 feet as you can see in the link. Kings 11-9 connectors work great with the 1855A as well.

http://www.belden.com/pdfs/03Belden_...s/19.78_78.pdf

I am happy for a nominal cost to make up any length BNC for anyone here and I typically can send them the same day.

It is more likely that you will have a problem with poorly crimped connectors, or problems with the camera or recorder than problems with 10 feet of coax cable.

Jeff
Jeff Silverman is offline   Reply With Quote
Old August 1st, 2009, 02:23 PM   #15
Major Player
 
Join Date: Oct 2006
Location: York, UK.
Posts: 224
Cables.

Thanks Jeff. Reminds me of cooking up my own hifi cables! Speaking of connectors, I'm not a big fan of the ones one a few of my Canares. Had better invest in some high quality DIY, like you.

J.
Justin Benn is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

Professional Video
(800) 833-4801
Portland, OR

B&H Photo Video
(866) 521-7381
New York, NY

Z.G.C.
(973) 335-4460
Mountain Lakes, NJ

Abel Cine Tech
(888) 700-4416
N.Y. NY & L.A. CA

Precision Camera
(800) 677-1023
Austin, TX

DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > The Tools of DV and HD Production > External Video Recording Solutions > Convergent Design Odyssey

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 10:56 AM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2017 The Digital Video Information Network