On Sat, Feb 12, 2005 at 04:12:50PM -0500, Andrew Gallatin wrote: > > I've been lurking, reading the archives for a month or two now, and > I'm finally ready to start building my HD Myth box. Right now, I am > attempting to choose the HD tuner card I will use. > > My current setup is a Zenith c32v37 HDTV with an integrated ATSC (and > QAM) tuner. I just put a ChannelMaster 4228 in the attic, and my OTA > reception is now pretty good but I have large signal fluctuations on > some stations at times. The signal meter seems to jump from 90% to > 30% and back in a few seconds on the problem station. > > I think this is a classic symptom of multipath, and I've heard that > the tuner you are using can really make a large difference in working > around multipath to give you a stable signal. Since the Zenith is > "old" (label on the back says it was made in fall 2003), I'm hoping that > the tuner in one of the HDTV tuner cards might be better. > > In other threads, I've heard things like the air2pc pulled in stations > that the pcHDTV-3000 did not. But were those weak signals stable? > Which does better for reasonably strong stations with multipath?
Drew, and others... The antenna, amount of cable, and amplifier will make more of a difference in signal quality than the type of ATSC card. Period. My first recommendation is get the antenna out of the attic. An attic is a good place for increasing mutli path, weaking your signal, and doing the things you don't want. My personal experiece with my antenna was that I could get almost no signal in my attic. I moved it out and signals became very clear (And I live at the base of mountains and a canyon so I'm *very* prone to multi path). I'm 20 miles away from the towers, use a very low quality yagi ($20 radio shack 36 inch) run 250' of rg6, through 2 1-4 splitters all with no amplification and get all signals over 70% (One is 72% and another 78%. The rest are 88+%). For you, and others, moving your antenna outside will also help more than trying to pick "which card is better at ...." in my experience. If you remove noise you're putting into the cable running to your tuners, this will do more than using a card to correct your errors. An additional note, not all splitters are equal. I've found a 15 year old cheap hardware store 1 to 4 splitter works better than a "gold plated" radio shack one (by 7-8% signal quality loss). I've found amplifiers don't do much good for signals over 80%. I've also found that I have one HD-2k card that on 1 channel doesn't tune as well as my other 4 cards (4-8%). But I do know it's not a problem if I do everything else right. Oh, I've found every 50' of cable is about 5% signal quality loss on signals less than 85% normally, 1% on signals over 85%. My HD-3k card though gets the best signals I should note. If you want to know which card is better, I recommend you figure out which chips they use and go do research outside of the myth community. What I know is the hd-3k chip is much better at removing multi path than the hd-2k. I know that I have a lot of multi path where I am and my hd-2k's work just fine. I know that if you spent the time moving the antenna outside instead of doing research, you would have better results. :) I should also note, Multi-path typically not a big issue and it sometimes is blamed for things it's not responsible for. You could be getting multi path, or you could just have the frequencies bend so slightly that it makes it between the crack in 2 shingles, or misses a nail, or goes between two ceiling braces just right sometimes and you get a better signal for a quick moment, or it could be MP. If you describe your community setting and distance from the tower I could give you a better idea if it's MP or something else. --Brandon
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