Here's My Potential Distro Plan, What Do You Think?

[genepensiero]

hey all.

looking to update our video distro through our campus. like many of you, we've built a system over time, adding a screen here and there, sometimes mickey mouse, sometimes compromising to make it integrate with our system.

right now we have a Kramer VP724ds distributing to 8 different locations. the feeds are split up, some are Coax, some are VGA, some are vga over cat5. feeds terminate at either TVs, Monitors or Projectors.

i'm limited in my knowledge. i know there's some hardcore SDI guys on here, and i'd love to hear their feedback of my plan.

all of the runs are greater than 15 feet. 3 of them are above 200 feet.

my hope is to have as few go-betweens as possible. right now we have converter box after converter box and i know it's affecting the signal.

here's what i've preliminarily drawn up:

Kramer VP-724DS ( http://www.kramerelectronics.com/pro...ued.asp?sp=237 )
to
Kramer TP-210A ( http://www.kramerelectronics.com/pro...l.asp?pid=1101)
to
Kramer TP-124 ( http://www.kramerelectronics.com/pro...el.asp?pid=405 )
to monitors /vga tvs / projector

give me your thoughts. if i'm missing an obvious deal, let me know. everything listed is Kramer because i've had good success with them, but i'm happy to look elsewhere as well.

my goal is to have as clean a setup as possible, with as few components as possible.

would love to have our campus feed in HD. our current camera is a Sony HVR-A1U HDV camcorder (1080i).

[genepensiero]

bump!

any thoughts? i have one local guy suggesting i carry everything over SDI, but from what i understand, SDI has to be run in series, correct?

we have RG6 cable run all over our campus, but it's multiple runs that all terminate at our sound table, so we'd have to re-route all of that to chain SDI together, right?

is there a reason that i shouldn't use CAT6 to distribute audio & video?

would love any feedback you guys have.

[tdangelo]

Gene,

Not sure what you mean by " SDI has to be run in series," or "[all the RG6] would need to be rereouted to chain SDI together." Can you explain that?

[Brad Weber]

Originally Posted by genepensiero

i have one local guy suggesting i carry everything over SDI, but from what i understand, SDI has to be run in series, correct?

we have RG6 cable run all over our campus, but it's multiple runs that all terminate at our sound table, so we'd have to re-route all of that to chain SDI together, right?

Unless the displays have loop-through SDI inputs, SDI would not be daisy-chained, it would have to be run to each display. Also, the RG6 cable is not necessarily SDI compatible cable, it may be intended for cable/CATV, you'd probably want to verify the specific cable and it appropriateness for HD/SD-SDI.

Since you apparently have a VGA source and I doubt that your displays directly accept SDI, you could convert your VGA signal to HD/SD-SDI, use an SDI Distribution Amplifier (or two) to send a signal to each display and then use SDI-to-VGA converters at the displays. The longer 200'+ runs would probably require some of the lower loss SDI cable.

Originally Posted by genepensiero

is there a reason that i shouldn't use CAT6 to distribute audio & video?

Yes, but simply because I would recommend CAT5 or CAT5e for this application. The tighter twist rate of the pairs and greater differential twist rate between pairs that makes CAT6 preferred for data transmission are a negative for analog VGA-over-UTP transmission as at longer transmission distances they can introduce skew. Basically, over a long run each pair in a CAT6 cable is a different length so the signals on each pair arrive at slightly different times. Since the receivers you linked do not have skew compensation, you would ideally want to use low skew or even skew-free cable but otherwise CAT5/5e would be much preferred over CAT6.

[genepensiero]

Originally Posted by tdangelo

Gene,

Not sure what you mean by " SDI has to be run in series," or "[all the RG6] would need to be rereouted to chain SDI together." Can you explain that?

a local guy who works in video distro claimed that HD-SDI distribution has to be done in a chain. i didn't quite understand, so i'm trying to read up too. i'm not finding much information corroborating that SDI has to be daisy-chained.

[genepensiero]

Originally Posted by Brad Weber

Yes, but simply because I would recommend CAT5 or CAT5e for this application. The tighter twist rate of the pairs and greater differential twist rate between pairs that makes CAT6 preferred for data transmission are a negative for analog VGA-over-UTP transmission as at longer transmission distances they can introduce skew. Basically, over a long run each pair in a CAT6 cable is a different length so the signals on each pair arrive at slightly different times. Since the receivers you linked do not have skew compensation, you would ideally want to use low skew or even skew-free cable but otherwise CAT5/5e would be much preferred over CAT6.

thanks for that information brad. we have plenty of CAT5e to use, so i'll probably head in that direction.

we're not married to the kramer scaler, but that's the one component we have right now.

what would you recommend for a router/switcher?

[Esoteric]

Yeah, it depends on exactly what you are looking to accomplish. We do installations with full HD going over SDI (recommended) and we also do CAT5e installations using something like Ed's Just Add Power System. It all depends on budget and what you are actually expecting the equipment to do.

[tdangelo]

Originally Posted by genepensiero

a local guy who works in video distro claimed that HD-SDI distribution has to be done in a chain. i didn't quite understand, so i'm trying to read up too. i'm not finding much information corroborating that SDI has to be daisy-chained.

Maybe there is a missunderstanding. No, SDI does not need to be daisy chained.

[genepensiero]

--
i'm familiar with Kramer Electronics and their SDI options are limited.

what HD-SDI distros do you guys recommend?

[tdangelo]

If looking for a HDSDI distribution amplifiers the Cadillac is Evertz. Leitch (now Harris) is very good. Aja makes good stuff that is not too expensive. Blackmagic makes stuff that is pretty cheap.

[Esoteric]

We mostly sell Blackmagic, but the ATEM products sometimes have issues with multiple resolutions.

[dmerchen]

Originally Posted by Esoteric

We mostly sell Blackmagic, but the ATEM products sometimes have issues with multiple resolutions.

The biggest thing we found with Blackmagic is that you need to make a commitment to a particular resolution system wide. As you noted they don't much like having multiple resolutions, as they lack scalers.