Dear Big Picture Big Sound,
I just purchased a new Sony 52 inch Bravia XBR TV and we moved it from one wall to another wall in the same room which was about 10 feet away. We purchased an extension RG6 digital cable that connects satellite and digital sources to make up for the 10 feet, once we turned the set on we received no satellite signal, we are having Direct TV come out and reroute the satellite cable on Saturday the 5th of July, but until then, can you tell us how to get the satellite signal.
I see no reason why an extension cable wouldn't work. I assume you're talking about using a female to female coax adapter (aka a "coupler") at the end of the existing coax cable plugging the new extension cable into that, and plugging this into the back of your existing satellite receiver in its satellite input jack? And now the satellite receiver is not receiving anything? If you're plugging it in the way I've described above, then it should work unless you've got a defective cable or coupler.
Is this a high definition DIRECTV box or standard def? If it's standard def you need to upgrade to a high definition box for use with the new TV otherwise the picture quality is going to be pretty poor. Make sure the DirecTV people know this before they come on their service call so they bring the HD box with them. It's possible you'll need a new dish as well which they can do for you.
If this is a standard definition DirecTV box, then you can temporarily leave the satellite box where it was and buy a long RCA A/V cable (these are the red/yellow/white cables that come free with many A/V components), putting this between the satellite receiver and the TV, plugging the cable into your AV1 or Video 1 input on the TV. Select Video 1 on your TV to view the picture. Again, this is only a temporary solution to get a picture but it will not be high definition.
And I hope you're not talking about using a coax connection between the DirecTV box and the TV itself and trying to tune the signal in on channel 3 on the TV? That's the worst possible way to connect a satellite receiver or cable box to a TV. This modulates the separate A/V signals from the satellite receiver into one combined signal, losing stereo sound and most of the video quality in the process only to have to separate it back out again at the TV. The only place you should ever use RG6/coax cable with DirecTV is between the satellite dish and the satellite receiver.
Ideally you want to connect the high definition DirecTV receiver to your TV with an HDMI cable. This will get you the best picture and sound quality with just a single thin cable. Most of the HD DirecTV boxes I've seen come with an HDMI cable in the box, which will save you from having to buy an expensive aftermarket HDMI cable.
For more details on how to hook up HD components to an HDTV, see part II of our "How to Hook Up Your HDTV" article series.
Hope that helps.