I have one of the Vieras and did nothing but add the extrernal HD antenna.
It might be a stretch but the only adjustments I've done was to have it scan for only HD channels (we pick up old channels from Mexico here) and move the antenna direction to get a few more channels.
Not much has changed since I watched my dad put up an antenna in the 1960s but I am finding folk that are rediscovering the old skills of installing roof top antennas, cables and yelling down about "is it better now?"
Bob
We've recently cut the cable and do the digital antenna thing. I read a user post on amazon.com about "adjusting your tv's tuner" when searching for channels through a digital antenna. Can someone shed some light on what "adjusting your tv's tuner" entails? I have a brand new Panasonic Viera 37in. Thanks in advance!

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