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-   -   Need a composite video splitter (https://www.dvinfo.net/forum/open-dv-discussion/467559-need-composite-video-splitter.html)

Tripp Woelfel November 11th, 2009 06:04 PM

Need a composite video splitter
 
I need to split the analog SD composite video signal from a camera to source inputs to two different NewTek TriCasters. We may have the option to go SDI out but I think the TriCaster inputs will need to be composite to match the other two cameras. The feed from the camera will run at least 50 meters before it gets to me.

I'm not much on the old school analog video requirements so I have more questions than answers. I don't know what that long run will do to splitting the video, or any other considerations so any insight you could offer would be appreciated.

Chris Soucy November 11th, 2009 07:19 PM

Hiya Tripp............
 
Long time, no speak.

Not sure of the circumstances of your setup but to my mind the simplest and most practical solution to your problem would be mini Wireless Video senders/ receivers.

No cables to trip over and the signal gets to it's destination just as it left.

One transmitter and two receivers on the same channel and it's job done.

Most seem to be designed to work off wall worts as they run continuously, but given the small energies involved, modifying to work off batteries wouldn't be rocket science.

Must be dozens or even hundreds to choose from on the American market.


CS

Perrone Ford November 11th, 2009 07:27 PM

50 meters is a pretty fair run... especially for low powered wireless devices. I'd be using some high quality coax for a run that long, or fiber. Or placing a repeater in the middle. Is this open air, or do you need to go through walls?

Shaun Roemich November 11th, 2009 07:28 PM

Tripp: 50m isn't a big deal. I run 200' lines routinely. The voltage drop of two loads would be the only thing that would concern me. Do you have access to an analog composite distribution amplifier? I HAVE used the Radio Shack versions (RCA connectors) in the past when I've been DESPERATE with reasonable success.

Perrone Ford November 11th, 2009 08:00 PM

Shaun,

Thanks for the heads up. I was thinking about length of run for HD-SDI which is what comes off my camera.

Belden makes a nice guide here:

http://www.belden.com/pdfs/Techpprs/...Data_Rates.pdf

Shaun Roemich November 11th, 2009 08:47 PM

Thanks for sharing, Perrone. Just goes to prove that cable DOES make a difference. I don't have mine in front of me but I know I spent a reasonable amount to have it made up. Milspec stuff... 95%+ shielding. I used to research that stuff, then I just started paying people to make it up for me.

I think I STILL have copper strand slivers in the bottom of my feet from making literally over 100 BNC cables. Chucked most of them over the years when I realized my crimping sucked! I get my fabricator to use compression fittings exclusively now and carry screw on BNC ends in my kit JUST IN CASE.

Tripp Woelfel November 11th, 2009 08:53 PM

Hey Chris... Howaya? Don't really want wireless. Cable is already run so that will be simpler and I'll be missing all the potential wireless headaches.

Perrone... No walls. Basketball arena, but walls aren't really a concern since the wire is run and it's permanent, high quality coax.

Shaun... What I have now is one cable and I know that ain't enough. No amps or anything. Based upon what you describe, I think you're lasering in on what I'm looking for. I suspected that the loss from splitting might perish the signal. I need a strong signal and a splitter. The run out of the splitter will be less than a meter.

I'll check out the Radio Shack options, but I'd rather go with something more professional grade. Suggestions?

Chris Soucy November 12th, 2009 12:04 AM

I'm good mate............
 
Thanks for asking.

Finally managed to keep logged on to DVinfo for longer than a gnats fart, so can actually post again, which is a plus, been out for over three months!

(Went over to Australia for three weeks, leaving my system quietly auto updating itself in my absence, came back to chaos).

I'd stick with Radio Shack quite frankly (depending on budget, of couse).

Composite and Professional don't really sit too well in the same sentence in this day and age. You can spend a fortune on Pro gear, but to what end?

Buy it, try it, don't measure up, take it back.

My only concern is that anything designed for composite O/P won't be designed to feed into a 75 ohm co - ax cable (I have no idea what they're designed to feed into, the cable runs usually being very short) but I'll be suprised if it's 75 ohm, long run.

BTW, WTF are NewTek TriCasters?

Sounds like something you'd use to move the fridge/ freezer out for cleaning!

Regards,


CS

Shaun Roemich November 12th, 2009 01:30 AM

Quote:

Originally Posted by Tripp Woelfel (Post 1446079)
I'll check out the Radio Shack options, but I'd rather go with something more professional grade. Suggestions?

The "usual" big names - Extron, AJA, Ross etc. all make DA's. Should be able to rent one from your local pro house or AV supplier.

And Chris: composite is alive and well in multicamera live switching in SD over here. SDI hasn't caught on yet for industrial level stuff and multicore/fibre is the domain of the mobile truck.

Composite feeds out of a camera should indeed be on 75 ohm cables with 75 ohm connectors (BNC).

Taking a T-connector to split the signal is likely to cause you signal loss UNLESS you're able to control 75 ohm termination at both Tricasters in which case you MAY get by but the DA is a much safer bet (and will give you better signal to noise characteristics).

Giroud Francois November 12th, 2009 03:22 AM

for about 70$ Kramer is making a nice composite distributor.
Video Distribution Amplifiers (DA'S)

Tripp Woelfel November 12th, 2009 07:24 AM

Shaun... Thanks! I'll look into those names. We'll probably buy one since we'll need it for the whole season. Some additional research is making me a bit smarter on this topic so I think I can take it from here.

Chris... The TriCaster is a NewTek family of products. Think of it as a production truck in a box... sort of. The TriCaster name comes from its ability to live switch an event along with graphics and other goodies and send three different outputs; standard video/audio, record to the on-board hard drive and push a Web stream all at the same time. It's a pretty remarkable little box. We're doing a dress rehearsal of a live scrimmage next Friday so that will be my first crack at using it on a real event.

Battle Vaughan November 12th, 2009 08:20 PM

Tripp, fwiw I've taken NTSC feeds from pool cameras at about 300 ft. into a multbox with no problem. If you get hum you can buy a Humbucker or eqivalent (Markertek is one source) fairly cheaply. Any decent video and audio distribution amp should do the trick for splitting your video, here's a source (Bhphotvideo sells some of these) Composite and S-Video Distribution Amps | HDMI Cables | DVI Cables | VGA Cables| Audio Video Cables | Computer Cables / Battle Vaughan

Shaun Roemich November 12th, 2009 08:41 PM

I've used Kramer as well. Budget minded for pro gear. Thanks Giroud!

Jay Massengill November 16th, 2009 02:58 PM

As Battle said, definitely watch out for ground-loop hum in the coax connected video devices that are likely powered by AC circuits in different parts of the building. And of course don't try to defeat the safety grounds on your AC cables. Use a good video humbucking transformer.
The best way to use the distribution amp would be a short run from the source to the DA, then the long run over two separate cables (especially if your DA has adjustable outputs).

Shaun Roemich November 16th, 2009 10:07 PM

Jay is correct. I've also seen DA's with simple Proc Amps on them that can come in handy.


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