My projector has a single RG-6 cable with RCA terminals running to it from the console space in the front of the room. I wanted the cable to be hidden as much as possible and I didn't run an HDMI connection because I couldn't find a way to terminate HDMI terminals on unterminated stock HDMI cable, which is how I did with RG-6 and RCA terminals. Currently, I output the video signal out of an older model DVD player, which has a single RCA output. The video quality is good and the projection size on the wall is 98# in diameter.

However, I would like to buy a streaming video box, such as Roku HD, so that I can stream movies and music from YouTube and Netflix onto my home theater system. I ruled out Apple TV as it only has HDMI out. Roku HD has HDMI, which I can use for audio, but it also has three composite ports.

My question is: can I either just use one of those three ports to connect to the single wire projector connection or can I somehow convert the signal by using all the three and then some kind of adapter? If not, what are my options for streaming with this kind of video connection setup?

  • I'm confused. A typical composite video output is almost always accompanied by two composite audio outputs (yellow, red, white/black). If the projector has RCA input, and the Roku has RCA output, what's the problem?
    – Tester101
    Commented Nov 10, 2014 at 17:35
  • so are you saying i can just hook the yellow video output to my RCA/coax connection and it'll be fine?
    – amphibient
    Commented Nov 10, 2014 at 17:36
  • No, I guess I'm saying I'm confused as to exactly what connections are actually available on each device. If you included a photo of the connectors, or the model number of the devices, then folks might have a better understanding of what's going on.
    – Tester101
    Commented Nov 10, 2014 at 17:39
  • The Roku box has 3 composite video outputs (yellow, white, red). The projector only takes one rg-6 cable in because that is what i ran through the ceiling. That rg-6 (or coaxial cable) has RCA terminals on both sides. I am saying that the projector cannot input anything other than something that can travel via a single coaxial cable (so HDMI is ruled out)
    – amphibient
    Commented Nov 10, 2014 at 17:42
  • the projector connection type is sealed, i.e. invariable at this point, as it has been run through the ceiling.
    – amphibient
    Commented Nov 10, 2014 at 17:43

2 Answers 2


The Roku HD has 3 RCA plugs (not "composite outputs"). One (yellow) is a composite video signal, the other two (red/white) are stereo audio (left/right), clearly labelled:

Roku HD ports

So direct answer: Yes, you can use your RG-6 cable to get the composite video signal up to your projector. However, composite video is pretty low quality (480i), so don't expect greatness.

Alternatives to get HD video

  • Bite the bullet and run an HDMI cable through the wall (seriously, too bad you didn't put in a conduit at least!)
  • Use an HDMI-over-coax extender. This could use your existing RG-6, but does require installing a small box at your projector with power.
    • Alternatively, HDMI-over-cat5e/6 extenders are available, if you ran Cat5e or Cat6
  • Use a wireless HDMI sender/receiver pair (again, requires adding a powered box at your projector)
  • Put the Roku box at the projector
  • That last might be simplest answer, given that the projector is already mounted and has power, and the Roku is small and lightweight. If you're always operating it with the remote, it doesn't really matter where you put it in the room; IR reflects off walls pretty well.
    – keshlam
    Commented Nov 10, 2014 at 23:24
  • Thanks a lot for the great answer. Do you know if I can user the HDMI to output just the audio if I am using the yellow RCA port for the video already? IOW, would using just the yellow video port somehow stop the release of the audio through the HDMI ? Because I would like to output the audio to my receiver via the HDMI
    – amphibient
    Commented Nov 10, 2014 at 23:31
  • I don't, sorry. I have a Roku 2 box somewhere but it only has HDMI. Maybe you can use your Receiver to downscale to 480i/composite, and output that to the projector? At least you'd only have to change inputs on your reciever, not both receiver and projector (I hate having a system that requires multiple inputs on different devices to be changed).
    – gregmac
    Commented Nov 10, 2014 at 23:43

There are two common video connection types that use RCA-style plugs:

Composite video uses a single connector, typically yellow, to send the video signal. This is really the lowest quality video connector available, capable of sending only about 480i (which is half the resolution of a DVD, and downright pathetic compared to the requirements of high-def video).

Component video uses 3 connectors, typically red, blue, and green, to send the video signal. Component video is analog (unlike HDMI, which is digital), but is capable of sending full 1080p high-def video.

Neither of these standards includes audio, (like HDMI does). Analog audio RCA connectors are typically red and white (or sometimes red and black), and are in addition to the video connectors.

Unless you have absolutely no option, I would strongly discourage you from using composite video. The quality is quite poor by modern video standards, although of course you also need to consider the resolution of the projector. Does your projector support component video? If so, there are HDMI-to-component adapters available (I have no experience with them) that you could use from the Roku if you need to be able to terminate the cables yourself.

  • Roku has composite: support.roku.com/entries/…
    – amphibient
    Commented Nov 10, 2014 at 18:52
  • right now i output a single wire connection from the DVD to the projector. would what you are suggesting be of lower or higher quality than that?
    – amphibient
    Commented Nov 10, 2014 at 19:02
  • @amphibient: if by "single wire" you mean a yellow RCA plug, then the quality will be exactly the same. (Of course, a "single" HDMI cable is very different). If you're happy with it now there's not any need to do anything differently with the Roku, but if it were me setting this up I would do it with HD cables, either HDMI or composite cables + an HDMI-to-composite adapter for the Roku. If your source and destination both support HD video, you're already 95% of the way there. (This assumes your projector is capable of HD, but based on your comments about HDMI I'm assuming it is.)
    – Hank
    Commented Nov 10, 2014 at 19:16
  • @amphibient: Also, it's not clear to me whether you can hook up the Roku as you proposed... I don't know if the HDMI side outputs audio if you're using the composite for video.
    – Hank
    Commented Nov 10, 2014 at 19:21
  • that's a valid concern, i will call their tech support to find out
    – amphibient
    Commented Nov 10, 2014 at 19:33

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