I have a 52" HD TV Sony Bravia hooked up to my Comcast Cable Box via HMDI.
I have another 15" HD TV set up near my treadmill, about 20 ft away from my cable box.
The 15" HD TV does not have HDMI connection, so I connected the 15" HD TV to the cable box via component cable.
Both TV's will operate at the same time.
The question is: Am I compremizing my HD signal by this set up?
Note: I only operate one HD TV at one time. One is off while the other is being used.

You have nothing to worry about.

HDMI is 100% digital. Ones and Zeros.

Component is analog.

The modules within the cable box that generate each of these signals operate independently and derive the signals that they output from the raw digital data coming from the cable company. The Component converts to analog via a D/A converter.

The component and HDMI portions of the cable box are on the digital bus within the box regardless of what is plugged into them externally. What's plugged into one CANNOT affect the quality of the other.

At 20 feet, since component is an analog signal, use good quality component cable to ensure you don't lose anything in the cable (but on a 15 inch TV, it might be hard to see much difference between cables anyway). In any case, the presence of anything plugged into the component output (even with a horrible quality cable) will have no effect whatsoever on the HDMI output.

How does it look to you? On a 15" TV... I don't think it's a major compromise.

Just curious, which is it? (not that it will make a difference)
Both TV's will operate at the same time.
The question is: Am I compremizing my HD signal by this set up?
Note: I only operate one HD TV at one time. One is off while the other is being used.

How does it look to you? On a 15" TV... I don't think it's a major compromise.

Just curious, which is it? (not that it will make a difference)[/QUOTE]

I don't see any noticable differences, but was just wondering cause the more you look at it the more you can convience yourself that their 'is' a difference.
A techy at Ultamate Electronics told me it would deminish the quality of the HD signal on my Bravia.

Buy hey!, thanks for the information. I'll take your word for it.

Both on or only one on... there shouldn't be a difference. (other than subliminal suggestion by the "tech" and the capabilities of the TV's themselves)