You don't say which model, but I found this:
"So when you connect a basic analog cable that comes out of the wall, without a cable box, an HDTV scans for both analog and digital channels (the digital channels are usually higher numbers and come with a - or . and more numbers). Pretty much every other HDTV I've seen so far stores the analog and the HD channels together and allows you to scan (surf with channel up/down) through both types in a unified list. This is the biggest problem with this TV - it stores digital and analog channels in separate lists and treats them as two separate inputs: the same way as, say the HDMI inputs. This way there are input choices for Analog TV, HDMI 1, HDMI 2, Component, AV, AV2 (side), USB, Digital TV. Note the position of the analog TV place and the Digital TV place - they are separated by all other inputs.
Here is where it gets ugly - there is no way to switch between analog and digital channels without changing to the correct "input". Things are made severely bad by the dreadful remote control, which has no dedicated input selection buttons. It relies on a single "input" button, which cycles through all available inputs.
There is no way to deactivate unused inputs and the TV is pretty slow during changing them, pausing for more than a second on each change."
Here:http://www.epinions.com/review/Sanyo_DP26649_TV/content_502191525508
ChicksFan, August 2011