Hi,

I have a Toshiba 65HM167 and an HD HomeRun. Both have QAM tuners and are hooked to the same cable feed (Charter in Long Beach, CA). Charter uses QAM-HRC.

The HD HomeRun gets more channels. The Toshiba doesn't even get all the locals (I.e. CBS missing). It also maps a dozen of the QAM channels to channel number 0.

Anyone know why this might be or have more info about QAM?

Thanks,
Mark

First they need to be unencrypted. Most of the channels here are encrypted so my 65HM167 can't receive them,(Although all my local channels are unencryptrd so the TV can recive them)or can't decrypt them but that is what I use my Series 3 tiVo for.

I have 4 recent vintage HDTVs, all with QAM tuners, in the same house connected to the same cable and no two receive the exact same set of digital channels off my Comcast cable feed and the mapping to channels numbers also vary between the sets.

Digital tuners are very sennsitive to signal strength and will not receive a signal at all if the strength is too low or too high. Since the signal strength degradation caused by a splitter may be more on some outputs then others I suggest you try bypassing your splitter. If that solves the problem on the unit receiving less channels than you could put an amplifier ahead of your splitter.

Digital tuners are very sensitive to signal strength and will not receive a signal at all if the strength is too low or too high. Since the signal strength degradation caused by a splitter may be more on some outputs then others I suggest you try bypassing your splitter. If that solves the problem on the unit receiving less channels than you could put an amplifier ahead of your splitter.
In my case I have the cable feed amplified and I have verified that I have a relatively strong (but not excessive so) signal level at each of my QAM capable HDTVs. There really is a difference in what each HDTV's digital tuners will detect that is not an issue of signal strength (I have tried less and more amplification to test this). It seems to be more related to how the individual cable company is multiplexing the digital channels and/or the channel mapping the cable co. is using. Of the QAM capable HDTVs that I own (Panasonic Plasma, Toshiba LCD, JVC D-ILA rear projection TV, and Vizio LCD) the least expensive model (20" Vizio I have in the kitchen) is able to find the most digital channels. The JVC D-ILA RPTV is a close second and the Panasonic Plasma and the Toshiba LCD only find about 1/2 as many as the Vizio and JVC.