Yes, you do need a tuner that is capable of receiving HD signals. Depending on where you live, you will have one or more choices of receiving HD signals. 1) OTA over the air 2) Direct TV, Voom, or Dish Network Satellite TV 3) your local cable company. In all cases if you will need a HD tuner if your set (in this case your projector) is only HDTV-Ready. This only means your display device does not have a HD tuner. Most HDTV's that have a tuner will make it clear that it is included. The lack of a tuner in HDTV's makes the price lower for the device and most people will more than likely have a tuner from a cable or satellite service. here is a FAQ and a good source for answers to any other questions you have.
http://www.crutchfieldadvisor.com/ISEO-rgbtcspd/learningcenter/home/tv_faq.html#5
Hi,
I am thoroughly wiped out researching the components for our new HT system. We have decided on the Panasonic AE-700U video projector and now I need to choose the AV receiver. What I'm trying to figure out is ... do I need the receiver AND a "video processor" to be able to receive cable and project it? I want to be able to receive and project HDTV signals in addition to playing DVDs and video games. I keep reading reviews and they say things like the AV receiver has HDTV-Ready Component Video Input/Output but I can't tell if I need something else to change channels or not.
Thanks for any help you can give me.

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