can i use any cable for component cables? [Archive] - Audio & Video Forums

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liejian
08-14-2006, 05:06 AM
hi guys,

i wanted to hook my dvd player to my new plasma tv. It supports component video but i dont want to buy the cables since i have so many regular RCA (audio, video) cables laying around.. Can I just use these? If not, can someone suggest a good place to buy inexpensive yet pretty good quality cables?

thanks!
LJ

likeitloud
08-14-2006, 05:52 AM
No, the cable impedance is wrong on rca audio cables, component video requires 75 ohm
inpendance, common rca cables don't support that requirement. For cables on a budget
check out partsexpress/ar and ixos.

L.J.
08-14-2006, 05:56 AM
You can use 3 video cables. I did this at a buddies house recently. You can also pickup some cables at RadioShack or Homedepot for pretty cheap.

edtyct
08-14-2006, 06:00 AM
Besides the 75 ohm (or thereabouts) standard, video cables must pass a higher bandwidth than audio cables. However, if you have old composite video cables lying around, you might try them in your YCbCr configuration. Standard video doesn't need as much bandwidth as HD; older composite cables should comprise an adequate component connection, assuming that the cables' basic engineering is okay.

noddin0ff
08-14-2006, 07:08 AM
If I understand... if you use audio rca cables that are not 75 ohm, you get some of the signal reflecting back from where the cable meets the TV component input. The reflections bouncing back and forth on the cable can give you 'ghosting' images where you see faint 'ghosts' of the images on screen that are shifted to the right a little bit. If you don't see this with basic cables, you don't have a problem. Can edtyct comment?

edtyct
08-14-2006, 07:19 AM
Hi noddinoff,

Yes, a substantially lower impedance will create reflections that can distort the signal. How low? I really don't know; resistors on equipment can apparently smooth out such anomalies. It may be important to note that video cables have a hard time achieving the 75-ohm standard, but at these frequencies, hitting it on the nose isn't essential. Nonetheless, cables should be engineered as carefully as possible to approximate the standard to avoid the problem that you mention, as well as others. The bandwidth issue, however, is sufficient on its own to ban audio cables from the video domain.