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Stallions Satellite and Antenna - TV Reception Solutions
 
Frequently Asked Questions
 

Question: Do I need to get a special TV antenna or can I use my current antenna to receive high definition television (HDTV) broadcasts?

Answer: Your current TV antenna should work fine for receiving digital broadcasts if you can receive your analog broadcasts clearly without any ghosting. DTV (digital) broadcasts are very sensitive to reflected waves, which appear as "ghosts" in analog broadcasts. If reflected waves are present when trying to watch digital broadcasts "tiling" and complete channel loss can occur.

If ghosting isn't a problem, but some or all of the channels are snowy, then installing either a preamplifier, a new higher gain TV antenna or both may help to clear up not only your current analog reception, but will ensure that you receive a reliable digital signal.

Question: I am trying to receive digital over-the-air TV and I bought a Channel Master 4221 4-bay UHF antenna. My TV gives a "Signal Strength" indicator ranging from Weak to Strong with 10-12 bars in between. Where I am located I have a hill and trees between me and the TV stations' towers.

The Signal will be around 5-7 bars showing a great picture then the Signal Strength falls to zero (the picture freezes or pixilates or disappears) then comes right back with the Signal Strength jumping back to 5-7 bars. Sometimes this happens every 10 to 20 seconds and other times it may go hours and be just fine. I never see it drop to 2-3 bars and come back up. It seems like it's all or nothing.

Is this a characteristic of interference? Will an antenna amplifier help?

Answer: Before recommending a solution we need to identify the exact cause of your digital reception problems. The most important question is how well do your ANALOG channels come in. Now you might be saying to yourself "I don't care how well the analog channels look just so the digital channels come in", but you will after reading further.

With analog channels you can actually see if the signal is weak (snow) or if there are double images (ghosts) on some or all of the channels, whereas with digital channels you either get a picture or you don't. The digital signal strength indicator on nearly all TVs and/or HDTV tuners doesn't tell you what's really going on with the signal from one channel to the next.

The FCC designed the North American over-the-air digital broadcast standard (8-VSB) to replicate an existing analog TV station's coverage area. Each analog channel was granted a second channel (VHF or UHF) to broadcast their digital signal on. The standard was designed so that if you could receive an analog station reasonably well without a lot of snow or any ghosting you would be able to lock in the station's digital signal as well. However, if your analog channels are full of snow, then it's safe to say that your digital channels are also weak in signal strength and you should first consider installing a pre-amplifier to increase the incoming signal levels. If your analog channels have ghosts on them (which digital channels don't tolerate at all) then keep reading.

Multi-path interference can be seen on analog channels as double images or "ghosts". The cause of ghosts is that you receive two signals - one directly from the TV station's broadcast antenna and a second, weaker, reflected signal a split second after the original signal. The difference in timing between the primary and secondary (reflected) signals causes the ghost to appear. An example of a reflected signal would be a signal bouncing off of a nearby obstruction, such as a building, hill or water tower and being picked up by your antenna.

There are a few things you can try to fix this problem. The first would be to realign your antenna so that the ghosting is eliminated or at least minimized on the analog channels. If there are stations you wish to receive that have towers located in different directions you may either have to install a rotator or combine a second antenna with the first one.

If the stations you want to receive are all located in the same direction and realigning the antenna did not help, try moving the antenna to a different location and try different heights. Many times having the antenna higher may not always be better since signals tend to travel in layers.

If none of the above suggestions help you may either need a more directional antenna which will reject bounced signals coming from other directions, a combined antenna array, or both.

Question: I live in an apartment and I can just barely get reception. What type of antenna can I use outside my apartment window?

Answer: Although the best solution would be to connect your TV to the apartment building's master antenna system, not all buildings have one. So the next best solution would be to install a Winegard Sensar III GS-2200 TV antenna. This is a small bi-directional antenna that has a built-in amplifier to help "boost" weaker channels.

Question: I have an antenna in the attic and it is hooked up to our TV in the family room. I have wires in place in several other locations in the house and would like to hook these up to the same antenna. Can I use a simple splitter or do I need any type of special equipment?

Answer: Depending on how many TV outlets you have in your house, you should be able to use a simple splitter to connect all of the outlets. We generally recommend that a distribution amplifier be installed if more than four outlets will be connected at the same time. Splitters come in various output models, depending on how many total TV outlets will be connected.

Question: I recently installed a 900 MHz 2-way radio system and I am getting interference on my TVs. My current preamplifier has a frequency range up to 900 Mhz, which I believe is the problem. Would a VHF-only preamp eliminate the interference?

Answer: Although replacing your VHF/UHF preamplifier with a VHF-only model may eliminate the interference, it may not. What it would certainly do is greatly reduce the signal level on all of your UHF stations. Even if you live in an area that doesn't have any UHF TV stations right now, many VHF stations have been assigned UHF channels to start broadcasting their digital signal. That means that when the stations stop broadcasting an analog signal in a few years they may choose not to go back to VHF and stay on their newly assigned UHF channel.

So instead of switching preamps, I would suggest installing a Microwave Filter Company model 3322-806/860 Lowpass Filter between your antenna and the preamp. This will pass frequencies from 50-806 MHz, while reducing the signal level on frequencies from 860-1000 MHz by 40 dB. This filter can also be used to eliminate interference from a nearby cellular telephone tower. This would also be a great example of when to use quad shielded coax cable, which can help to eliminate radio frequency interference (RFI).


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