The Digital TV Conversion

Many consumers are noticing that they are missing channels they once received perfectly fine with an analog broadcast.

However, some TV viewers may find that their reception improves with digital, because digital signals don't attenuate in the same fashion as analog ones. In fringe reception areas, where they may get weak, poor-looking analog reception, it could improve with digital. But the down side is that with digital you tend to either get the signal or you don't, so poor digital signals might completely disappear.

There are several factors that can contribute to losing a channel:

1. You have an outdated antenna and need to upgrade.

2. The nature of a digital signal is different than analog - it is generally all or nothing. This means analog channels with a significant amount of snow or picture disruption may not come in. This is because the digital transmission is too degraded for your converter box to read. People are calling this the "digital cliff effect".

3. Some broadcasters are reducing the geographic footprint of their digital signal. This is tech-speak for, they just aren't sending signals as far out as they used to. Often, a consumer will pick up another affiliate from a neighboring town (you lose the NBC out of Boston but pick up the Hartford NBC station). However, some may loose a channel altogether. Consumers Union has dubbed this a "digital dead zone."

Consumer Reports advises consumers to check with their neighbors if they notice a missing channel. If your next door neighbor gets the channel, it's likely an antenna issue. If many people in your area are missing the same channel, consumers should call the local broadcaster to troubleshoot.

Digital TV does not have a weaker transmission system; in fact it's more efficient than analog and, for a given frequency allocation, needs less power to cover the same area at higher quality.

However, because the received digital signal has to be above a certain level before any picture can be displayed, people in rural areas who may have watched analog TV with a lot of "snow" or picture interference may need to upgrade their antennas.

Also, many (but not all) digital stations are broadcast on UHF frequencies, which are susceptible to blockage from hills, tall buildings, and even trees. To avoid erratic DTV reception, it's important to have the right UHF and/or VHF antenna for the stations you want to receive. In rural areas this will usually need to be an outdoor directional antenna that must be pointed in the right direction. With the right antenna, DTV gives viewers higher quality picture and sound than analog, and usually more program choices. For information on selecting the right antenna go here.