First, I need to point out that Terk HDTVi and HDTVa is not the same antenna. The HDTVa is the HDTVi with amplification. With this little detail taken care of, I have to say both work amazingly well.
I live in a concrete building with no direct line of sight towards the signal. Even though I live in the middle of the city and the signal should be strong, the concrete walls probably make the signal so weak that I have to get reflected signal.
Previously, I have used Terk TV-1 antenna, which, although is a pretty decent piece of equipment, did not guarantee a good watching experience. I could only get about a dozen channels. The TV-1 is mostly designed for VHF, which currently carries major analog channels, whereas major digital channels are mostly on UHF.
It was time to try the Terk's HDTV line of antennas. I was originally going to get the HDTVi, but decided to get the HDTVa. Upon receipt, I did try it in the non-amplified, HDTVi mode first.
The antenna is larger than it looks on the picture, yet still manageable. Its log-periodic UHF element looks cool and can be positioned vertically or horizontally. What is not apparent from some pictures is that the antenna has VHF dipoles that can be very long when extended.
The antenna is solidly built, but it is a little unstable ¨C it is really easy to tip it over if you touch it, especially with dipoles fully extended.
The HDTVi connects directly to the TV, whereas the HDTVa has a little ¡°power injector¡± box. You connect the antenna to it and the cable form the box to the TV with another cable to the power outlet.
I use this antenna with my Hitachi P50H401 50-inch plasma TV. Even with no amplification, I got twice as many channels as before, albeit some of them were freezing or becoming blocky. And after I connected the amplifier, the signal meter on my TV showed 95-100% signal strength (45-70% before that, with no amplification).
Although the noise is also amplified and amplification does not free you from having to position antenna in a certain way to catch a direct or (in my case) reflected signal, the result in my case was excellent reception of about 20 channels and ok reception on another 5 or so.
Updated 12/2011: I have used this antenna for 3.5 years, with great results. It also was able to withstand an earthquake that made it fall off the hight of approximately 4 feet on the carpet, with no damage. I also dropped it a few times accidentally with the same result.
Pros: Excellent performance, reasonable price, looks nice, does not take too much space.
Cons: Not very stable foundation.
I am extremely happy with this antenna. Despite looking small and dorky, it works perfectly well with excellent non-amplified reception (HDTVi) or amplified (HDTVa). I highly recommend the former if you expect good signal strength and the latter if you expect weak signal.
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