Chicago's HD is a VHF and UHF market, so you must use a VHF/UHF antenna. The stations will be changing around frequencies in February, but they will remain VHF UHF. I have messed around with a lot of these indoors units with similiar results, they all have the same basic design. Two VHF dipoles, or rabbit ears, and a UHF loop, which works fine for most people. But the best design I have seen is the
HDTVA, it takes the award winning UHF yagi design from the
Silver Sensor and adds the rabbit ears. Since the majority of the signals in Chicago are still UHF for HD this is a great antenna.
-Mike