question about amplifiers, i'm reasonably sure I need a vhf/uhf/fm amp, but i've found ones of various amplification, is there any benefit with getting a 30db boost (is this even reasonably, that sounds way high) vs a 24 or even 10db boost? ratshack has the Philips PM61111 for 30$ and is a 24db boost, but i found a unit on Froogle for 7.50 that gives a 10db boost has bandwith from 54-890mhz; the signal will be split with a -3/7/7 db loss splitter, with the two 7 db loss sides going to my capture box. a 10db boost would still give me a +3db over the current signal, which is fine for error free captures. (the capture program lists the strength at 33db or so after the signal passes through a -3.5db splitter if that means anything)

Get whatever boosts the signal enough for you to get it cleanly. Try it without any amp at all to confirm that you actually need one. The cable co sometimes helps out customers in cases like this - the signal is being split so many times within the house that it needs amplification.

Since you said QAM, you must mean CABLE, rather than OTA, which is ATSC.
Why do you think you need a Cable Amplifier???

Does your HDTV have a signal level indicator???
The 33 dB number is probably SNR (Signal-To-Noise Ratio)...
which would be marginal....35+ dB would be better.
Does this improve if you remove some RF Splitters???

Cable Amp may help if you have weak cable signal....
But low SNR may also be due to poor cable ground at entry point
and/or leaky RF connectors letting in outside interference.

Also, maybe you are still using some old RF Splitters,
if so, upgrade with 1000 MHz (or higher) splitters may help.

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Because CABLE occupies nearly every channel position with a very strong signals,
a different kind of amplifier is needed, called either a CABLE AMPLIFIER or a DROP AMPLIFIER.

An OTA Preamp is intended for very weak signal levels and can be overloaded by a Cable signal.

Cable (aka Drop) Amplifiers are available at R-S, Lowes and other DIY Home stores.....
with a variety of gain levels and number of outputs:
http://www.radioshack.com/sm-1-to-4-bidirectional-cable-tv-amplifier--pi-2103093.html
http://froogle.google.com/froogle?q=electroline+cable+amplifier&btnG=Search+Froogle

Along these same lines, I’m missing one QAM station with my Hauppauge HVR-1250. All other QAM stations have good signal strength. I get the station in question with no problem on my HDTV in another room. I removed all switches and ran the main cable straight to the HVR-1250, and am still missing the one QAM channel.

Would an amplifier help me receive the missing channel? If so, any suggestions on specific amps? Thanks.

I've found that one (QAM) channel was encrypted by Charter in a way that my Sony thought it was not, and another set knew it was.

This channel is pay per view and should have been encrypted ... and now is.

Perhaps without identifying the cable company, would you consider sharing the channel? Perhaps that will get more intelligent comments.

I've found that one (QAM) channel was encrypted by Charter in a way that my Sony thought it was not, and another set knew it was.

This channel is pay per view and should have been encrypted ... and now is.

Perhaps without identifying the cable company, would you consider sharing the channel? Perhaps that will get more intelligent comments.

the channel I'm unable to find is my local CBS.

the channel I'm unable to find is my local CBS.
Have you tried entering your zip code at silicondust to find your QAM channels?:
http://www.silicondust.com/hdhomerun/channels

If that doesn't help try your local reception thread:
http://www.avsforum.com/avs-vb/forumdisplay.php?s=&daysprune=&f=45