Quote:
Originally Posted by bigbangbaby
a friend of mine has since helped me set up a Qterra 22-421HD Outdoor HDTV Antenna in my attic which is about 30-35 feet from the ground. Here are the specs of the Qterra antenna:
- HDTV & SDTV reception
- wideband reception
- Frequency: 45-860MHz
- Gain: 25-30dB
- Output Impedance: 75
- Standing Wave Ratio: <=1.5
- Power: AC 110v
Here's what the antenna looks like:

|
From the looks of the antenna, it is a clone of a 4 bay bowtie antenna. It is definitely NOT good at VHF (ch 2-13, frequencies 54-216 MHz). Bowtie antennas like this are good for UHF frequencies (470-806 MHz), so I don't see where they get off claiming frequencies down to 45 MHz.
The antenna gain itself is probably in the range of about 12 dB in UHF frequencies and about -15 dB (yes, I mean negative gain) at VHF frequencies. The 25-30 dB of gain they are claiming is probably the gain of their built-in amp.
An amp is actually a really bad idea in your situation because you have some very strong local analog stations. Signals this strong will overwhelm just about every amp on the market. You really need an unamplified antenna.
Quote:
The coax cable is connected to the antenna and we tried 2 scenarios:
(1) we split a coax cable, connected it to the other cable that is built in to the AC adapter, and then connected it to my TV;
(2) connected the coax cable directly from the antenna to the TV.
|
The amp needs to be powered in order to pass any signal at all. Most amps act like a dead circuit (attenuating signals rather than passing them through) when no power is applied.
The antenna and power adapter should have come with a clearly marked DC-passing coupler. One port is designed to take power in and pass it through to another port up to the antenna. A third port (with no DC power allowed through) passes just the TV signals to your TV.
If you just used an ordinary splitter in your first scenario, it might not have passed any power up to the antenna (or maybe the wrong voltage if power was passed to both the antenna and your TV simultaneously).
Quote:
In both scenarios, we were only able to get the 9 following channels:
05 CBC
09 CTV
19 TVO
25 SRC
41 Global
47 OMNI 1
52 CKXT
57 CITY
69 OMNI 2
|
It sounds like either the amp was unpowered and attenuating most of your signal, or the amp was powered but being overloaded by the strong local stations.
Quote:
I have a feeling that either: (a) this antenna is crap; or (b) we set it up wrong, it should be plugged in, and it's pointing in the wrong direction?
|
Given the deceptive marketing of the antenna specs, I'd lean toward it being a lousy antenna, combined with the fact that the amp was probably not working.
Quote:
Should I just trash this antenna and get a better one? Is there an antenna you can recommend that has great reception from inside an attic?
|
Yes, I'd go with a different antenna. You definitely need to avoid using anything with an amp, being so close to some very strong signals.
I would try an antenna like the Winegard HD7696P and aim it directly at Buffalo (compass heading 156 degrees). This is a directional antenna, so hopefully, the strong local stations will be attenuated a bit since they would be coming in through the "side" of the antenna (where it is less sensitive). An even larger antenna (HD7697P) would be even more selective and might work even better if you can get it to fit in your attic.
Just in case the local signals are still too strong for your TV's tuner to handle, you might want to install a variable attenuator (like
this) near your TV so that you can adjust the power levels down when necessary.
I'm not sure you'll be able to adjust this setup to receive all of the signals simultaneously since there are really three main clusters of channels (at 85, 217, and 156 degree compass headings). You might get lucky and find a sweet spot that happens to get all three clusters simultaneously (mostly pointed at Buffalo and getting the closer stations through the "sides" of the antenna). If that doesn't work, then some of the stations will be sensitive to your antenna aim. If it's important for you to be able to get all the channels from all directions, then you may want to consider adding an antenna rotator.