I know this may have already been asked so sorry if it has.

I know this may have already been asked so sorry if it has.

You want to reword that and add some more details to your question please.

How are you receiving non HD channels on your HDTV today?
Are you referring to some of the PBS channels or network aqffiliate digital sub-channels that will be broadcasting in 480i instead of in 720p or 1080i?

Whatever you get "digitally" today, will not be any "clearer" after 2/09.

If anything, mine are getting less clear over time, due to the excessive addition of subchannels.

I am not an engineer but I heard or read that a digital signal unlike analog does not change quality from the transmitter. You either get the signal in all of its quality or you don't get it, or it may even drop out on you. However it is digital so there can be no loss of quality like what happens with analog.

If this is NOT true then please explain.

The SIGNAL may be stronger in fringe areas, since there will be less CCI and ACI when all those analog transmitters go dark. If you're getting breakups due to signal issues and you live a significant distance from the transmitter site, analog shutoff could cure your problems.

The same goes for stations that are running their DTs at less than authorized power and height. Assuming they ramp up to their authorized limits around the time of shutoff (not all will), you may see an improvement in signal strength.

As for picture quality, as noted above, artifacts not caused by differing signal strengths will be unchanged with analog shutoff. Picture quality will most likely improve over time with the advent of better encoding technology ...and complaining advertisers.

Analog transmission have a maximum of 330 horizontal lines. Digital SD transmission have a maximum of 640 horizontal lines. So there is a POTENTIAL of greater resolution. However, unless the source of the video at the station's transmitter is better will any improved picture be realized.

Rick R

Standard NTSC 480i analog tranmissions have about 640 "dots" in each of 480 horizontal rows.
Digital ATSC 480i encoded video has either 704 or 480 dots in each of 480 horizontal rows.
See the following Link which describes both:

http://www.hdtvprimer.com/ISSUES/what_is_ATSC.html

Aanalog treanmissioin can suffer from poor PQ due to low singal strength (snow) or interferance (artifacts).
Digital are either received or not received and do not suffer from either of the above.

NTSC does not have 640 lines of horizontal resolution. It is only about 330. The table is incorrect.

Rick R

IIRC... NTSC is capable of the resolution(s) described in the chart. But, NTSC broadcast resolution is typically ~330.