I just got a new CRT Tv and it has component hook ups(Y, Pb, Pr). My digital source has Component out, buy I only have RCA a/v cables(Red, White, and Yellow). Could I use those cables for the hook up or could I mess something up by useing the RCA A/V cables?

You can try them, you won't hurt anything but I would really recommend getting a set of component cables!!

The red-white-yellow cables aren't balanced. The yellow cable may be a good quality 75-ohm cable, but the red and white are probably lighter electrical wire rather than proper video-quality cable. If you have three identical yellow cables they would probably work, but even those might have slightly different loss levels. A proper set of component cables is generally the best way to go.

Used a/v cables for a while with my year-2000 CRT RPTV, even with a few cable couplers to create ~6' lengths, and it worked okay for HDTV. But switched to component cables, which have accurate 75-ohm impedance, after a few months. Never measured it, but suspect the component cables would deliver slightly higher resolution if you compared using a 1920X1080-line test pattern (such as HDNet's Sunday 6:50 am ET resolution wedges (http://www.avsforum.com/avs-vb/showthread.php?postid=5175424#post5175424)). -- John