KFUO: ANALOG VS. IBOC
To illustrate how spectrally
inefficient IBOC-DAB is vs. analog, KFUO (850 kHz)
LOCATION:
10 miles northwest of Concordia
Seminary
Receiver: General Electric Superadio III
Dial Heard
with KFUO in analog mode Heard
with KFUO in IBOC mode
800 KREI Farmington, MO (clear) KREI
810 WHB Kansas City, MO (clear) WHB
820 WCSN Chicago, IL (weak) Wiped
out by KFUOs IBOC sidebands
830 KOTC Kennett, MO (fair in Stereo) Wiped out by KFUOs
IBOC sidebands
840 In both instances, this frequency is
wiped out by KFUOs sidebands
850 KFUO has excellent sound KFUOs
sound quality is tinny, at best
860 In both instances, this frequency is
wiped out by KFUOs sidebands
870 WINU Shelbyville, IL (weak) Wiped
out by KFUOs IBOC sidebands
880
890 WLS Chicago, IL (good) WLS Chicago, IL (very
poor with KFUO interference)
900 KFAL Fulton, MO (clear) KFAL Fulton, MO (clear)
In the case
of WHB, WCBW and WLS, KFUOs IBOC sidebands are
interfering with their signals. (QRM is another term for interference.) In this
case, the stretch between 820 and 870 kHz is wiped out by the IBOC sidebands.
Now, heres
a second location
much closer to KFUOs transmitter
site.
LOCATION: 7700 block of
One mile west of Concordia Seminary
Receiver: Jensen AM/FM receiver with
CD player
Dial Heard
with KFUO in analog mode Heard
with KFUO in IBOC mode
800 KREI Farmington, MO (clear) KREI
810 WHB Kansas City, MO (clear) Wiped
out by KFUOs IBOC sidebands
820 Image from KFUO Wiped out by KFUOs
IBOC sidebands
830 KOTC Kennett, MO (fair) Wiped
out by KFUOs IBOC sidebands
840 In both cases, KFUOs
sidebands make this frequency unusable
850 KFUO with excellent audio quality KFUO with tinny audio quality
860 In both cases, KFUOs
sidebands make this frequency unusable
870 In both cases, KFUOs
sidebands make this frequency unusable
880
890 WLS Chicago, IL (fair) Wiped
out by KFUOs IBOC sidebands
900 KFAL Fulton, MO (fair) KFAL
Fulton, MO (with severe KFUO
interference)
In this
case, KFUO is wasting more spectrum space at closer range. Analog radio is more
efficient, from a spectral point of view, than IBOC (or any other digital form
of radio). This proves, once and for all, that AM frequencies are not suited to
digital radio (and neither are shortwave and FM, for that matter). For more on
the truth about IBOC-DAB, go to the Digital
Disaster Web site, put together by the
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to IBOC: Myths and Facts