Kmox: analog vs. iboc

 

Until April of 2000, KMOX (the Once-Mighty ‘Mox) broadcast in the technologically advanced and near-CD quality sound of AM Stereo, using Motorola’s proven C-QUAM system. KMOX began broadcasting in low-definition digital (as opposed to high-def C-QUAM) in the spring of 2006. Here’s what damage the conversion has done during the daytime on an analog receiver at Hazelwood, MO:

 

Frequency    With KMOX in Analog mode (Mono/Stereo)                With KMOX in Digital mode

1070 kHz        KHMO Hannibal, MO (good to fair signal)                         Severe interference from KMOX’s IBOC sidebands

1080 kHz        WRYT Edwardsville, IL (clear)                                             Nearly inaudible due to KMOX’s IBOC sidebands

1090 kHz        WCRA Effingham, IL (fair signal)                                        Wiped out by KMOX’s IBOC sidebands

1100 kHz        Clear                                                                                       Wiped out by KMOX’s IBOC sidebands

1110 kHz        Analog sidebands from KMOX                                           Analog/digital sidebands from KMOX

1120 kHz        Center frequency                                                                   Center frequency

1130 kHz        Analog sidebands from KMOX                                           Analog/digital sidebands from KMOX

1140 kHz        WVEL Pekin, IL (Fair signal)                                               Wiped out by KMOX’s IBOC sidebands

1150 kHz        WGGH Marion, IL (Fair signal)                                            Wiped out by KMOX’s IBOC sidebands

1160 kHz        WYLL Chicago, IL (Poor signal)                                          Wiped out by KMOX’s IBOC sidebands

1170 kHz        KUGT Jackson, MO (Fair signal)                                        Severe interference from KMOX’s IBOC sidebands

 

Since KMOX is a 50,000-watt Class A station, the potential for interference is greater. The IBOC sidebands could also affect the reception of stations on 1050, 1060, 1180 and 1190 kHz. KMOX’s conversion to IBOC has hampered the ability of WRYT Edwardsville, IL to be an effective radio apostolate to the St. Louis Catholic community. Along State Road 162 near KMOX’s transmitter site in Pontoon Beach, IL, WRYT’s signal is wiped out by KMOX’s digital sidebands. Some of the gaps may be filled, thanks to Covenant Network’s recent acquisition of KHOJ (1460 kHz) in St. Charles, known as “Heart of Jesus Radio”.