ATSC vs. QAM - your opinions?

[barnabas1969]

I'm interested in the possibility of putting up an antenna to get my locals using ATSC tuners instead of QAM, as I get them today.

I've been doing some reading about QAM vs. ATSC-8VSB. Basically, what I've found is that both occupy the same bandwidth of 6MHz. However, due to modulation differences (mostly the extra error-correction in 8VSB), QAM has double the usable data throughput. So, using the same compression ratio in MPEG2, the cable company could effectively put two HD streams on one QAM channel, delivering exactly the same quality as those two OTA channels using ATSC.

Upon further research, I've found that my cable company (Brighthouse Networks - Central Florida) is putting anywhere from 4 to 6 streams on a single QAM channel. Some are standard definition, some are HD. There is a mix of both on most of the QAM channels. So, this leads me to believe that the cable company is sending the local HD channels with more compression than those channels are using OTA.

What's your opinion? Do you think it would be worth the expense of putting up an antenna to get the less-compressed locals? I'm about 40 miles from all the transmitters... and conveniently, most of them are grouped together so that I would not need a rotator. I've done some checking around, and it looks like it will cost me about $200.00 for the antenna, pre-amp, and other hardware. I was thinking ahead when I wired the house so I already have a 2nd coax run from my HTPC to the area where I would mount an anenna.

[richard1980]

In my experience, OTA transmission have been higher quality than my cable company retransmissions. But I'm sure it varies by provider/location.

[adam1991]

good luck finding an antenna solution that provides a usable signal for all your locals.

[makryger]

Atsc is the higher quality signal, but qam is the more reliable signal, with access to more channels with less blockiness. Although clearQam may be going extinct, so out may not be future proof

[barnabas1969]

good luck finding an antenna solution that provides a usable signal for all your locals.

There is only one local channel that I like to watch that doesn't have its transmitter located right next to all the others (they are all located in Christmas, FL)... and it is the one I watch least frequently. It is also closer than all the others, so I'm hoping that I can point my antenna at the group of transmitters located farthest away (40 miles northwest from me), and still pull in that one that is 28 miles west of me.

If not, then I could just use QAM for that one, or add a smaller 2nd UHF antenna pointing in that direction with a signal combiner.

Florida is flat, and I don't live in an "urban canyon", so why do you think I will have trouble?

[adam1991]

Experience.

But if you have a high quality outdoor antenna on a mast already, or are willing to install and maintain one, then get a cheap tuner and try it.

[bmblank]

I live in a rural area and have ota TV. I have a high gain antenna pointed at one tower, probably 60 miles away, give or take. Those two channels are right on the edge of my viewables. I'd say there's no problem about 75% of the time. The other channels are in the other direction 10-15 miles. Those come in clear as day.
I should also mention I live in a planned red pine farm and pines are notorious for killing radio signal.

I don't foresee any issues with going ota.

[barnabas1969]

I already have tuners that can receive ATSC. My QAM tuners can also receive ATSC. I have ATSC/QAM tuners on two cards, so I can just use one of the cards for ATSC and the other for QAM.

My question was is it worth the expense? It will cost me about $200 for a big enough antenna (according to antennaweb.org), a pre-amp, and mounting hardware. I already have the cable run to the location where the antenna would be mounted.

The antenna (AntennaCraft C490) is $90, pre-amp is $30, mounts are $10, gas-tube surge suppressor/grounding block $15. That leaves me $55 for a mast, ground wire, and about 15' of RG6 and some connectors. I checked Radio Shack and they wanted $30 for each 10' section of mast. I think that's ridiculous, so I'll probably just use a couple of pieces of 1.25" galvanized steel pipe... unless Home Depot or Lowe's has masts at a reasonable price.

[barnabas1969]

I live in a rural area and have ota TV. I have a high gain antenna pointed at one tower, probably 60 miles away, give or take. Those two channels are right on the edge of my viewables. I'd say there's no problem about 75% of the time. The other channels are in the other direction 10-15 miles. Those come in clear as day.
I should also mention I live in a planned red pine farm and pines are notorious for killing radio signal.

I don't foresee any issues with going ota.

How tall is your mast?
Which antenna are you using?
Are you using a pre-amp? If so, what model?
What part of the country?