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2. Over the Air: Your Antenna

In this new era of digital TV, there are good reasons to use an antenna to receive WKAR -- even if you already have cable or satellite service for viewing non-local channels.

With a digital TV and the right antenna, you receive all four WKAR channels; High Definition programs reach you in true High Definition; and, there is no monthly fee.

Good reception over the air can present some challenges. If you are experiencing reception troubles, here are some possible causes and suggested solutions.

Poor Reception -- Weak Signal vs. Multi-Path

The two main causes of poor reception are a weak signal or a multipath signal. Before digital TV, a 'snowy' picture was a symptom of a weak signal. A picture with 'ghosting' -- a faint duplicate of the picture -- was a symptom of a multi-path signal.

weak signal - snow	multi-path signal - ghosting	good signal - clear

One of the advantages of digital TV is that it completely eliminates snow and ghosting from your TV picture.

But weak and multi-path signals can still challenge your digital TV reception. With digital TV, the symptom for either is picture and sound that cut in and out or simply do not appear. Each problem has a different set of solutions.

Weak Signal
You may experience a weak signal from WKAR if:
- you are near the outer fringe of our FCC-estimated coverage area
- you are down in a valley
- large buildings, trees, hills, etc., are between your antenna and WKAR
- you are located very close to our WKAR tower
- you are in an area that is receiving interference from other signal transmissions

Why digital WKAR might seem weak, when the old signal seemed strong:
- You might have received a weak signal before, which reached you as a snowy image that was still acceptable for viewing.
- The physics of how the digital signal travels has some differences from the old TV signal.
- Temporarily (until June 13, 2009), there are signal overlaps at some outer edges of our coverage area while digital channels operate in the same crowded spectrum as the old analog channels.

Weak Signal - Suggestions

Reposition your antenna. The higher you can place your outdoor antenna, the better your reception will be. The FCC-estimate of coverage areas assumes an outdoor antenna at a height of 30 feet. If you are using an indoor antenna, try placing it near a window.

Invest in a new antenna. New antennas designed specifically for digital television are often much smaller than the rooftop antennas of the past. Compact antennas allows more flexibility in placement and can be easier to install.

Try an amplified antenna. An amplified antenna can boost a weak signal up to acceptable levels. But, if your trouble is actually multi-path interference (see below), an amplified antenna may create problems instead of solving them.

Be Patient. - After June 12, when all of the old analog signals get turned off, channels will be reassigned to use the newly available space, and interference at the outer edge of our coverage area will be minimized.

Multi-Path Interference
If you saw ghosting on WKAR-TV before digital TV, then your reception problem is probably due to Multi-Path interference.

Large objects can reflect a television signal. Any reflected signal reaches your antenna a little bit later than the signal that travels direct from our tower. With the old TV transmission, that second signal produced ghost images. With digital TV, the second signal creates interference with the first. The result is a weak (or non-existent) signal.

Multi-Path A signal traveling along Path B arrives later than the signal traveling along Path A, creating a ghost image for analog TV, and interference for Digital TV.

Large buildings in your area can create multi-path interference for an indoor or outdoor antenna. In the home, large metallic objects like refrigerator doors and silver coated mirrors can create multi-path interference for indoor antennas.

Reflected signals can be quite strong close to a broadcast tower, and so multi-path interference is common for those who live close to a broadcast tower.

Multi-Path Interference - Suggestions

Use a directional antenna. A directional antenna will receive signals only from one direction, ignoring reflected signals.

Reposition your indoor antenna. Raise the antenna above appliances and mirrors that might be reflecting the TV signal.

Do not use an amplified antenna. An amplifier can boost reflected signals along with direct signals, and so can be a cause of multi-path interference. If you are using an antenna with a signal amplifier, try disconnecting the power to the amplifier unit.

Reduce the signal strength. Reducing the strength of the signal may be the fix for you if your problem is caused by a strong signal from a nearby tower. An attenuator pad connected between your antenna and TV may reduce the signal to a level where the reflected signals no longer create interference. Antennuator pads are available at most electronics stores for a few dollars.

Selecting an Antenna: AntennaWeb.org
If any of the reception difficulties above suggest a new antenna or a new location for your antenna, additional help can be found at AntennaWeb.org.

AntennaWeb.org presents a map, customized for your location, of TV station directions and distances, and recommended types of antenna, based on the address that you provide. AntennaWeb.org is a Web site of the National Association of Broadcasters and the Consumer Electronics Association.

Visit:
www.antennaweb.org

For more information:
Antenna Installers in Mid-Michigan
CrutchfieldAdvisor: Choosing & Installing an Antenna for HDTV (Retail Site*)

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