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Over the air has been exceedingly hit or miss for me also. Even after the equipment the actual delivery seems very scattered. I know in my head that the delive

Over the air has been exceedingly hit or miss for me also. Even after the equipment the actual delivery seems very scattered. I know in my head that the delivery of digital with correction should be better than analog, but the experience simply is not. I am not a electrical engineer, so can anyone shed light on why the range for channels on digital is so much lower than it was with analog, also is weather much more impeding for digital than analog?

dmfdmf 13y ago
OTA can be tricky because its not as simple as just throwing up an antenna and calling it a day, the system has to be engineered. Check out www.tvfool.com for some great info on properly designing a system. Also, avsforum.com has some great info.
- frankydp 13y ago
  Thank you for these links.
VLM 13y ago
Lots of VHF broadcasters switching to UHF as part of the transition? Not all have done so, but "many" have. All things being equal, an ancient coax cable with X milliliters of water contamination or Y amount of corrosion will have more loss at UHF than VHF. Pretty much everything is more critical at UHF. Even antenna aiming. The other way its a problem, which is actually pretty funny, is marketing of "HDTV" antennas where HDTV means UHF only, which works great if all your local broadcasters moved to UHF with the transition; As you can imagine a UHF antenna doesn't work so well if you live in an area with one of the few remaining VHF-Lo band transmitters which you "need". To say this is a local issue would be an understatement. I'm sure you'd get a better answer from a neighbor than HN.
gvb 13y ago
The simplistic answer is that they are cramming a lot more information into less bandwidth. Analog TV resolution was 640 × 480 (approximately)[1] where digital TV is 1920 x 1080 [2]. Digital also aggravates reception issues because it doesn't degrade gracefully. Instead of "snow" and color issues, it goes all blocky and then takes a couple of seconds to resynchronize... if it recovers. The Shannon–Hartley theorem[3] relates the necessary signal-to-noise ratio (S/N) that is required to cram a given amount if information into a given amount of bandwidth. Digital TV uses a lot of compression to reduce the amount of information that has to be crammed through the pipe and extremely sophisticated encoding to cram a bunch of bits into each symbol (baud[4]), but, at the end of the day, you have to have an adequate S/N ratio (good enough reception) to decode the signal. [1] http://en.wikipedia.org/wiki/NTSC http://en.wikipedia.org/wiki/NTSC "Each frame is composed of two fields, each consisting of 262.5 scan lines, for a total of 525 scan lines. 483 scan lines make up the visible raster." [2] http://en.wikipedia.org/wiki/Digital_television http://en.wikipedia.org/wiki/Digital_television [3] http://en.wikipedia.org/wiki/Shannon%E2%80%93Hartley_theorem http://en.wikipedia.org/wiki/Shannon%E2%80%93Hartley_theorem [4] http://en.wikipedia.org/wiki/Baud http://en.wikipedia.org/wiki/Baud

dmfdmf 13y ago

OTA can be tricky because its not as simple as just throwing up an antenna and calling it a day, the system has to be engineered. Check out www.tvfool.com for some great info on properly designing a system. Also, avsforum.com has some great info.

frankydp 13y ago
Thank you for these links.

VLM 13y ago

Lots of VHF broadcasters switching to UHF as part of the transition? Not all have done so, but "many" have. All things being equal, an ancient coax cable with X milliliters of water contamination or Y amount of corrosion will have more loss at UHF than VHF. Pretty much everything is more critical at UHF. Even antenna aiming. The other way its a problem, which is actually pretty funny, is marketing of "HDTV" antennas where HDTV means UHF only, which works great if all your local broadcasters moved to UHF with the transition; As you can imagine a UHF antenna doesn't work so well if you live in an area with one of the few remaining VHF-Lo band transmitters which you "need". To say this is a local issue would be an understatement. I'm sure you'd get a better answer from a neighbor than HN.

gvb 13y ago

The simplistic answer is that they are cramming a lot more information into less bandwidth. Analog TV resolution was 640 × 480 (approximately)[1] where digital TV is 1920 x 1080 [2]. Digital also aggravates reception issues because it doesn't degrade gracefully. Instead of "snow" and color issues, it goes all blocky and then takes a couple of seconds to resynchronize... if it recovers. The Shannon–Hartley theorem[3] relates the necessary signal-to-noise ratio (S/N) that is required to cram a given amount if information into a given amount of bandwidth. Digital TV uses a lot of compression to reduce the amount of information that has to be crammed through the pipe and extremely sophisticated encoding to cram a bunch of bits into each symbol (baud[4]), but, at the end of the day, you have to have an adequate S/N ratio (good enough reception) to decode the signal. [1] http://en.wikipedia.org/wiki/NTSC http://en.wikipedia.org/wiki/NTSC "Each frame is composed of two fields, each consisting of 262.5 scan lines, for a total of 525 scan lines. 483 scan lines make up the visible raster." [2] http://en.wikipedia.org/wiki/Digital_television http://en.wikipedia.org/wiki/Digital_television [3] http://en.wikipedia.org/wiki/Shannon%E2%80%93Hartley_theorem http://en.wikipedia.org/wiki/Shannon%E2%80%93Hartley_theorem [4] http://en.wikipedia.org/wiki/Baud http://en.wikipedia.org/wiki/Baud