|Don's Home Products Digital TV antennas|
This a very cursory summary.
Many people are cutting their cable TV service and relying on Netflix and Hulu (see Internet TV).
In 2009 the US switched from analog to Digital TV format for broadcast over the air (OTA) TV.
First let me say that the frequencies didn't change so your old antenna should work.
Test with Winegard FlatWave FL5500Y Amped Indoor HDTV Antenna $80
I got 32 channels. In addition to those above I got
41.1,2,3,4; 51.3,5; 52.1,3,5,8; 58.1,3; 63.1,2,5,6,7,8,9
Channel 9 was marginal until I attached an amplifier. A cheap ($10) only got 58.1, 3 miles away in Warren.
Where I live on the top of the first range of the Watchung Mountains in Martinsville, NJ it is 29 miles to 1 World Trade Center (WTC) and 31 miles to the Empire State Building.
I have a line of sight to the WTC.
Mohu test from Bound Brook test - 43' elevation - 30-32 mi to NYC
Notice none are VHS channels (RF channel 2-13).
Most analog stations changed their RF channel in the digital conversion (and most VHF stations moved to UHF) for DTV, but were allowed to keep their old analog channel identification as their DTV or Virtual Channel.
I got 35 channels with a Mohu. Adding an amplifier didn't make any difference.
Antennas are either passive (connected directly to the TV) or amplified.
Amplifiers only help if you're far away (more than 20 miles) from the transmitter.
Don't be fooled by claims of astoundingly high gain. Some manufacturers are marketing small indoor antennas and labeling the boxes with gain numbers between 30 and 55 dB. This kind of unit is actually an antenna paired with an amplifier, and the gain value stated on the package is really the gain of the amplifier and not that of the antenna. While it is possible to improve reception by using a well-designed low-noise amplifier, most of the inexpensive antennas designed this way actually have cheap amplifiers and too much gain. That combination generally overloads the amplifier -- and potentially the receiver as well -- causing signal distortion that can degrade or eliminate DTV reception entirely. Most consumers are better off with a well-designed nonamplified unit, also known as a passive antenna. If television reception does require an amplifier, the best choice is a high-quality, low-noise model connected as close as possible to the antenna.
Wirecutter assembled a list of indoor antennas based on top recommendations on Amazon, as well as antennas recommended by respected reviewers from sources like Digital Trends, CNET, Tom's Guide, and Consumer Reports.In Consumer Reports tests, performance varied wildly--so much so that we couldn't really rank them in order of performance, as a model that did well for one tester couldn't pick up any TV signals for another.
The Mohu Leaf and Winegard Flatwave are both popular small flat antenas.
In HDTVexpert's tests 25 miles from the transmitter the Leaf was best. (I think the Flatwave was the un-amplified version.)
At Solid Signal Blog they say "So far, I don't see where one has an advantage over the other."
In Popular Mechanic's tests of amplified versions of both in New York City, the Flatwave got 48 channels, the Leaf got 35 .
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