Help with reception

zbz24 · 9-Jan-2010, 10:56 PM

Hi, I just bought a new LCD HDTV today along with a TERK omni-directional flat digital antenna. It's both VHF/UHF. I used the TV signal analysis and got http://www.tvfool.com/?option=com_wr...b32bb10a090dc5
My problem is that I am getting channels like FOX, ABC, and CBS but not CW or NBC. I noticed that they are all the same distance away and also the same azimuth. Will getting an amplified antenna help? There was one that was the same except with an amplifier for sale at Bestbuy for $20 more. Any help is appreciated. Thank you.

mtownsend · 10-Jan-2010, 8:37 AM

It looks like most of your channels are coming from just two main directions. There's one group in the north-east mainly serving Raleigh, and other group in the south serving places like Myrtle Beach and Florence. You have access to more than one Fox, ABC, CBS, and other stations depending on which direction your antenna is more sensitive to.

Just guessing, but it sounds like the Fox, ABC, and CBS stations you're getting now are coming from the south (WFXB, WPDE, and WBTW). The closest and strongest CW and NBC stations are north of you (WLFL and WNCN).

Note that even though your antenna is marketed as an "omni-directional" antenna, it is probably not completely omni-directional, and you might get different results by turning the antenna in different directions.

Quote:

Will getting an amplified antenna help?

For indoor antennas, amplification is usually not worth the money. These kinds of indoor antennas are generally low-gain antennas. If the antenna cannot deliver a clean signal to begin with, boosting such a signal hardly helps. In general, amplification is used to overcome long cable runs that come after the antenna, but with most indoor setups, the antenna is so close to the TV, that the amplification is not really serving any purpose.

If you're going to spend the money, you're better off investing in an outdoor antenna. Indoor antennas are always at a disadvantage compared to outdoor setups because: a) you lose a lot of signal going through the building, and b) the signal is more prone to "echos" and "reflections" from the environment (a.k.a., multi-path) that make it more difficult for your receiver to lock onto each channel.

I see at least three possibilites here:

Option 1) Try a very basic set of rabbit ears + loop antenna (~$15). Rabbit ears (for VHF) and loop (for UHF) antennas are sensitive from the "front" and the "back", so they're a little more directional than an "omni" antenna. This slight directionality and the ability to aim the antenna at the stations you want to receive means you can probably get a little bit more gain out of the antenna. This cheap solution might out-perform the Terk, although it is still subject to all the challenges of indoor reception.

Option 2) Use an omni-directional antenna designed for outdoor installation like the Channel Master 3000A or the Winegard MS-2000. These antennas would no longer be hampered by the indoor environment, and their electronics are probably better quality than the Terk.

Option 3) If just the Raleigh stations are enough to satisfy your needs, then you can use a more directional antenna like the Antennacraft HBU22 or Winegard HD769P and point it in that direction. The channels south of you might be strong enough to come in through the "back" or "side" of the antenna, but the main focus would be on getting a very reliable set of Raleigh network channels.

The directional antenna solution will just concentrate on one group of transmitters, but should provide more reliable reception. It's a trade-off of quality over quantity.

zbz24 · 13-Jan-2010, 6:47 PM

First of all thanks for responding, it gave me a better understanding of how all this works. I've decided to keep this antenna and the problem I have now is consistency. I haven't moved the antenna at all since my last post (by the window) and the channels seem to come and go. Last post I mentioned that I was missing NBC and CW but I did another rescan and now I'm getting both NBC (3 of them) and CW (can barely watch it, audio comes and goes and picture gets stuck a lot) and ABC is now gone. Do you know what could've caused this? Also the channel strength for the channels I always get is around 50/100 and right now for example NBC goes from 0-30/100, it will work fine for 5 secs, get stuck for 5 etc. Again, I haven't moved the antenna. Thanks again.

mtownsend · 13-Jan-2010, 10:55 PM

There are all kinds of things that can affect signal strength and quality over time. People walking by, cars driving by, trees blowing in the wind, changes in the weather, interference from power tools / appliances, and any number of other random factors can cause your signals to fluctuate.

If you are getting hit-or-miss reception on some of your channels, it probably means that you're operating too close to the minimum required levels. Either the signals are borderline too weak, or the signal is getting too much corruption from signal "echos" or "ghosts" that bounce around the environment. It looks like a little variation one way or the other is causing some channels to appear and disappear. To have a more stable viewing experience, you need to have more "signal margin" (stronger and/or cleaner signal) to deal with the natural signal fluctuations that are present in your situation so that you never dip below the point of seeing the picture break up or go away. A better signal will give you more of a "buffer" to help your tuner maintain its channel lock.

Just so you know, Terk has a reputation of making over-priced antennas that have poor performance. That doesn't mean that all of their antennas are bad, but in the majority of cases, they do not even publish their true performance specifications (because they do not stack up well against the competition). At this point, your current antenna is somewhat of an unknown because they don't provide any information on its true gain and antenna pattern. Just based on its size and construction, I really don't expect it to perform any better than a $15 rabbit ears + loop combo. I have not seen any information that would indicate otherwise. All antennas are subject to the laws of physics, and the Terk does not appear to have the size or structure needed to have better gain.

No matter which indoor antenna you go with, the signals can usually be improved by moving the antenna higher (i.e., second floor or attic). That is because the number of things that cause signal reflections/interference (e.g., walls, cars, trees, neighbors' houses, etc.) are usually more sparse the higher you go. In other words, as the signal comes to you over the horizon, the signal doesn't have to pass through as much "clutter" to reach your antenna if you install it higher up. If the signals can pass "over" stuff (like neighbors' houses) instead of "through" it, the signal strength and the signal quality will improve. You can test whether sticking the antenna out the window or moving it higher up makes things any better for you. Things should improve slightly, but it's hard to say how much improvement you need to avoid the channel pixellation/dropouts.

If you really must have an indoor antenna, I'd suggest returning your flat omni and getting either a Philips PHDTV3 or a Terk HDTVi (this is probably the only Terk I would ever recommend). Both of these antennas are copy-cat designs of a well known decent performing indoor UHF antenna. Both of these antenna models have added a pair of rabbit ears so that they can handle VHF frequencies as well (since WTVD and WBTW are on VHF channels).

Either of these antennas are about as good as it gets for compact indoor antennas. They are not "omni", but are rather slightly directional. This helps them get better gain than your existing Terk. Antenna gain is very much related to the directionality of an antenna. The more directional an antenna is, the greater its gain. These antennas need to be aimed at the transmitters you want to receive rather than being "omni", but the advantage is that you get a much better signal out of them.