10/16/09

The ClearStream4 from AntennasDirect.com

28.3” wide, 20.3” high, 6” deep, 5 lb.

Antennas that look the same work the same, true? Maybe.

The ClearStream4 is the most directional medium gain antenna available. The ClearStream2 is the least directional medium gain antenna available. The difference is profound. In an urban or close-in suburban setting, one of these antennas will be a good choice, and the other probably a very bad choice.

Beam widths (to the -3 dB points, for channel 30):

ClearStream 2 72º

Silver Sensor 64º

DB2 56º

CM4221 55º

ClearStream 4 33º

DB8 25º

4228HD 25º

Within 25 miles, if you saw ghosts on your analog channels then the “C4” is your best choice among medium gain antennas. The 4228 and DB8 are still more directional, but those are much bigger antennas. If there were no ghosts then the C2 is your best choice for avoiding a rotor when stations are in multiple directions.

The manufacturer claims the C4 will work up to 65 miles. It will. But most people beyond 30 miles need extra gain for rain fade and the mirage effect which can happen on sunny days. Most people beyond 30 miles will sometimes see dropouts with the C4 and will not be happy with it.

For channel 13, the ClearStream 4 outperforms rabbit ears. It might pick up channels 11 and 12. Do not buy it for channels 2-10. (The C4 works on channel 13 because of the two cross braces. But below channel 12 the balun betrays it.)

VHF Forward horizontal net gain:

The C4 employs the same balun and roughly the same harness as the DB8. That harness, which works so badly on the DB8, works quite well on the C4. The difference is that the support structure is plastic, not metal.

This page is part of “An HDTV Primer”, which starts at www.hdtvprimer.com