Great cables made by Andrew Ansnick

[William Demeritt]

Just wanted to give a quick shout out to Andrew Ansnick, who made me a couple ultra-thin BNC pigtails (24 inches long each) for a great price. Belden 9221 cable, great for tethered scenarios with HD-SDI out of camera, good build quality and well crimped. If you're looking to buy a few, he's got the tools to make 'em!

[Alex Kornreich]

Are you using these cables just for tethering, or for all the connections on your sled?

 

Reason I ask is I was talking to Jack at PRO about these great new superthin bnc cables I bought from Markertek, and how super excited I was to use them and clear a lot of clutter from my sled. And typical of Jack, always raining on my parade, he responds that I wasted my money and I should stick with my canare cables. He said even though they're 75 ohm, there's not enough shielding on the spaghetti cables to block out interference.

 

Have you or Andrew had any issues?

[William Demeritt]

I use them strictly for tethering on my sled. I haven't had any issues with signal degradation or loss, and I've been operating with my 9221 spaghetti cables right out of camera followed by 100-200 feet of BNC. If attenuation exaggerated signal loss or signal interference, then I would think I might have seen something by now.

 

On the other hand, I don't think I would use these cables on my sled for the sake of protecting against any interference that might happen. On my sled, for cables that make connections that happen no matter what setup (sled to monitor, sled to camera), I use cables from Pacific Radio built from Belden 1694A, which are 18AWG solid core.

[Twojay Dhillon]

If spaghetti's are prone to interference, then what use have they at all in the film/digi world? I've used Andrew's cables on a few projects and have had zero interference issues. Hell, my FIZ has had probs, but not his cables.

[Alex Kornreich]

Ok that's good to know. I just don't want to give my cinetronic any more reason to act up on me...

[Eric Fletcher S.O.C.]

Okay a few things cause HD-SDI breakup. Barrels, T's and 90 degree adapters need to be banished. You can get away with a 90 but only if it's a cable terminator ie it's the connector

 

Get rid of those and most of your HD-SDI issues go away

[William Demeritt]

To attempt to add to what Eric is saying (hope this goes well): the more breaks you introduce in the chain between the HD-SDI coming out of the camera and reaching the monitor, the greater the chance of drop in fidelity.

 

HD-SDI isn't an analog signal like CVBS, so if the signal degrades beyond a point where the monitor can recreate the image, it fails. Doesn't get dim (resistance is too high), doesn't get snow, doesn't distort like bad reception. Goes out.

 

If the camera would otherwise just go camera HD-SDI out to monitor in, on our sled (2 connectors = 2 breaks), this happens:

 

Modular PRO/XCS sleds (removable centerpost):

Camera out (#1), Sled topstage in (#2), Centerpost top LEMO (#3), Centerpost bottom LEMO (#4), Sled bottom BNC out (#5), Monitor in (#6).

 

Tiffen sleds (to the best of my knowledge):

Camera out (#1), Sled topstage in (#2), sled bottom BNC out (#3), Monitor in (#4).

 

Like Eric says, you add in a 90' elbow, you just created 2 more breaks in your line (Tiffen jumps from 4 to 6, PRO/XCS jumps from 6 to 8). Even the best crimped connections will give some degradation. Using a reclocking amplifier will help improve the signal, but those breaks also introduce opportunities for interference.

 

Using a barrel creates 2 more breaks. Gotta run 150' cable? 3 50' cables with barrels connecting = 10 breaks. You get the picture? It quickly becomes "only strong as your weakest link".

 

Belden 9221 (the spaghetti wires Andrew makes uses this) is 30 AWG stranded copper, very thinly shielded. I think the optimal cable for HD-SDI is Belden 1694A (18 AWG, solid core).

[Jeff Delvecchio]

You are correct about HD-SDI being unlike CVBS. And, yes, fewer connections = better signal. Most of the BNC adapters on the market are not true 75-ohm. I have almost never seen T's or L's that are 75-ohm. Look in the end of the female BNC...if the little tubular pin is supported all the way up with a piece of plastic, it's not 75-ohm. Connectors and adapters that are not true 75-ohm will cause loss in a HD-SDI signal stream. And, once it gets data losses...it's gone.

[Andrew Ansnick]

Thanks guys for the glowing reviews!

 

Figured I'd throw in a shameless plug here as well. Discouraged by the gouging that myself and other operators were facing from other cable manufacturers and distributors- I, like many others in our community, decided to make my own. The cable that I use for my spaghetti thin BNC's is indeed Belden 9221 miniature coax cable. I find that this cable is of much better quality then the commonly used Canare 50ohm stuff others are using to make their thin "HD" BNC cables from. In addition to Beldin 9221 being properly shielded (75ohm) for HD I find that it has a better memory then most thinner coax cables while still being very flexible.

 

As far as terminations are concerned, I use Kings brand BNC connectors which are also true 75ohm connectors, and are of the highest quality. I make sure to double strain relief all my cables to guard against years of abuse. I also label each cable's length for immediate identification and quicker access to the right cable.

 

 

I make these BNC cables in any length you'd like but most commonly am requested to do them in 6" increments (6", 12", 18", 24", etc.). Length is measure from connector end to connector end.

 

Please feel free to contact me for pricing.

 

Andrew Ansnick

310-993-0039

aansnick@gmail.com

[Noel Sterrett]

As far as terminations are concerned, I use Kings brand BNC connectors which are also true 75ohm connectors, and are of the highest quality. I make sure to double strain relief all my cables to guard against years of abuse. I also label each cable's length for immediate identification and quicker access to the right cable.

 

I don't disagree with the excellent technical points made above, but my practical experience has been overwhelmingly clear. In the early days of HD, I had a fairly extensive rack mounted patch bay full of SDI monitors, HDCAM and DigiBeta decks. Everything was connected via BNC cables which were fabricated a decade earlier for a standard definition patch bay. It all worked quite well for nearly a dozen years.

 

While I've had a great number of problems with BNC cabling, it has always turned out to be because of either damaged (usually crushed) cables or connectors, improperly made cables, or both.

 

With properly made and impedance matched cables and connectors (I use King also), the signal loss (db) for a given cable at a particular frequency varies primary with cable length. On a long run, high quality low-loss cable could be quite important. But in the case of a Steadicam rig, the distances are fairly short. So I had no hesitation running an HD-SDI signal to a Marshall HD monitor through the post on a standard definition Scout. With one of my very old cables attached and feeding it to the post from the top, the monitor worked as expected and reported a signal strength of 95%.

 

So while I'm not offering any guarantees, I plan on using thin BNC cables whenever and wherever I can.

 

Cheers.

[Jameson Johnson]

Over the short distances that we're running on our sleds, in my experience cables were not usually to blame. All the different places that we send SDI - recorders, transmitters, monitors, converters, etc - can take a toll on the signal strength if things aren't up to spec. And even if they are, most gear doesn't re-clock a signal, it merely passes it through. The only problems I've ever had with SDI on a rig came from bad connection points.

 

I've been a system engineer for quite a few years, and I've had to push HDSDI over pretty crappy coax for upwards of 250 feet without a problem. I've even used 50-ohm crap and had success with HDSDI; that was using a 6 foot chunk of cable though. It usually comes down to whether the transmitting piece of equipment can send out a signal strong enough to make it to the other end. If your cables and connectors are spec'd at HD, you shouldn't have a problem. All that said, stick with real HD cables and connectors, Kings and Canare are my preference. The thin BNC cables work great too. I've put them in installations bundled next to power cables and other signal types without a problem.

 

If you're getting interference into an SDI signal, check your connections, be sure they're tight. Check your sled too - if cables are built well, its usually the BNC terminal that's to blame. They get a lot of use with all the connecting/disconnecting sometimes they get tired and need to be reconnected. And all this business about 75-ohm being needed for HD - very true. But 75-ohm is the standard for SD also. CVBS on a 50-ohm cable can look pretty nasty too. If you have any 50-ohm stuff laying around, ditch it. There was a chunk of 50-ohm cabling that showed up quite a few years back when computer networks were running on BNC. Most recently I've seen 50-ohm cables finding their way into video departments from the audio guys. They use the 50-ohm stuff for antenna cabling.

 

Now, this is all just my experience. I know a lot of ops have different stories than I, but that's kinda what the forum is for, right?