Component video splitting

uranus

Active SatelliteGuys Member
Original poster
Aug 14, 2005
15
0
I want to hook three TVs in my basement to one receiver(622). I want them to display one channel on all three so thats not the issue. I also want HD signal on all three. I have connected my Projector with a component and one plasma with a 50ft HDMI. The third TV is also approx 50 ft away from the receiver. I cannot mess with the HDMI since I am pushing it distance wise anyway. Can I buy a component splitter and a 50 ft component cable without much loss? Will this be better than than simply running a coaxial cable to the third TV.
TV1-1080p Projector
TV2-1080p Plasma
TV3- 1080p- LCD
I will appreciate the expert opinion.
 
Years ago I split my Dish 3000's composite output with a set of individual RCA Y-adapters from Radio shack, ran it through a bunch of cable, and it worked fine.

Recently I split my Dish 622's component output with the same setup. The picture looks pretty good, (fine from normal viewing distance), but the stupidest thing happens. One run goes to a monitor on my computer desk. The other goes to an a/v receiver and then to a TV. When I turn one device on or off, the other blinks out for a few seconds! I don't understand that at all -- shouldn't ALL a/v inputs be sufficiently high-impedance as to cause no appreciable loading on the line? Also, sometimes the receiver will start to distort its output, as if the top inch or so of the picture is losing horizontal sync. This has, so far, never happened with the other monitor disconnected, so I can't say it has anything to do with the cable length.
 
You absolutely want a distribution amp.

Splitting with Y-adapters is not the right way to do it.

Unlike analog audio, composite and component video is impedance specific. RCA Y-adapters are meant for audio, which has very little impedance at the source. That means adding more devices in parallel draws more current but has little impact on the voltage. Component and composite video have a source impedance of 75 ohms, and a load impedance of 75 ohms. So adding another device in parallel will drop the voltage. Now you have less voltage going to each source. Since color depends on voltage level - full voltage means white - color will be screwed up.

To account for this, manufacturers implement something called AGC (automatic gain control), which attempts to sense the drop in voltage and correct for this. However, this is not a perfect technique, and the split signal will not look as good as the original.

In component video, the sync signal is also reduced in voltage. Thus, the sync signal can be screwed up too. AGC will try to compensate for it, but isn't always perfect. I believe this is why Jim S sees a sync problem.
 
Lets say I have to run 150' of component cable from my 622 to a bedroom tv. I would want the 1 in 3 out component video splitter mentioned above as it has an amplifier and is a distribution center, rather than splitter. I think that length requires a booster. Do I have to buy one, very long cable or can I get by with three 50' component cables that I can hook together with connectors? Would that be okay or will connecting these cables together cause a problem?
 
Try the cheap splitter, if your signaL isn't strong enough, then buy the amplifier.

See, but it's not at all about signal being "strong enough." Fact of the matter is your voltage WILL drop when more than one device is added in parallel off a single source. This will result in full voltage not getting to the device's inputs, and AGC will need to be used to correct. It will not be a perfect correction though, you will see artifacts.

A "distribution amp" is more than an amplifier. It also matches impedance. So each output is now 75 ohms, and lets you connect it correctly to the device's input.

Y-adapters don't work like CATV splitters. A CATV splitter will match impedance, resulting in a weaker signal but at the correct impedance. However, a CATV splitter isn't going to handle composite/component frequencies very well.

Lets say I have to run 150' of component cable from my 622 to a bedroom tv. I would want the 1 in 3 out component video splitter mentioned above as it has an amplifier and is a distribution center, rather than splitter. I think that length requires a booster. Do I have to buy one, very long cable or can I get by with three 50' component cables that I can hook together with connectors? Would that be okay or will connecting these cables together cause a problem?

You don't need a "booster" really...just a distribution amp...150 feet is fine for composite/component. If you're going over 300' or so I'd recommend using cat 5 and active baluns.

Coupling together 3 50' cables is essentially the same as a 150' cable, less tidy but there should be no performance impacts.
 
I use on of these to split my HDMI off of my 722k with no problem. I have a 50' HDMI running to a TV in the office and it works great. Got this and the cable from Monoprice


For only $84.50 each when QTY 50+ purchased - 1X4 PRO Series Powered HDMI Splitter (1.3b ATC Certified) | HDMI Active/Powered Splitter

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Don't give up on the HDMI going to more than one location. I have read where people are doing this sucessfully at 75'. I have another location that I just may try that lenght myself too.
 

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