In testing the review of the AVerMedia AVerTVHD MCE A180, we needed an antenna to receive OTA HD broadcasts.  HDTV signals are sent in UHF, so we decided to find the best UHF antenna available:  The ChannelMaster 4228.  The CM4228 is widely regarded as the best UHF antenna for pulling in distant stations.  It is an 8-bay bow-tie antenna with a large mesh grid reflector, providing excellent directionality and front-to-back rejection ratio. 

The CM4228 itself is fairly lightweight, large, and assembled using rivets and clamps.  There are two sets of four bow-ties, and both sets are tied together using the same steel wires/rods used as active elements.  Thinking that these wires/rods can interfere with the signal pattern, we decided to perform some surgery.  We modified the CM4228 by using a 300-to-75 ohm matching transformer for each set of bow-ties, and joined the signals with same-length RG6 coax to a 2-to-1 splitter/combiner. 

The CM4228 is shown below facing to the right, toward Mt. Wilson, mounted in the crawlspace above the lab's garage.  Mt. Wilson is about 35 miles away, and is the location of most of the TV transmitters in the Los Angeles area.  Unfortunately, those 35 miles of separation is not a clear, line-of-sight; the foothills from Cucamonga peak and all other mountains westward are in between.  Because the roof material is mostly wood and tile, a 1-3 dB drop in signal is to be expected versus mounting the antenna outdoors. 

ChannelMaster also provided a pre-amp to boost weak UHF signals - the 7777.  It consists of two-parts, the white, power-injector portion, and the black pre-amp which is designed to be mounted as close as possible to the antenna.  A standard 75-ohm coax cable connects the two.  We prefer using quad-shielded RG6 coax. 

The combination proved to be essential in extracting the most HD signal from the distant sources.  If you are located very close or have an unobstructed view of the HD/UHF transmitters in your area, a large antenna and/or pre-amp may not be necessary.  Many have had excellent results with rabbit-ears.  Another tip in maximizing the signal is to use impedance-matching transformers when connecting 300-ohm and 75-ohm transmission lines. 

Below are some screencaps of HDTV programs:

CBS-HD, 1920 x 1080:

"FUNimation" KSCI 18.3 HD, 720p:

Overall, the CM4228 and 7777 preamp works as advertised, pulling in distant HDTV stations better than rabbit ears or set-top antennas.  It's flat design allows for minimal wind resistance when mounted outside, and the pre-amp's separate power and amp modules maximize S/N ratio while keeping the power cord located where convenient. 

The verdict.....98%