Inovonics AARON 650, Installation & User Manual

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This returns you to the
Preset
Stations
menu where your en-
try will assume the top posi-
tion in the station list. The
arrow beside the entry
shows that this is the station now being received. To tune be-
tween multiple presets, highlight the one you want to receive
and push the knob to select the new frequency and its associat-
ed antenna, Reception Tool and alarm settings.
PASS-THROUGH vs. STEREO-REGEN
Most basic rebroadcast receivers will have a composite/MPX
‘baseband’ output, plus the obligatory left/right program line
outputs. These receivers are commonly connected to the base-
band input of the FM exciter to rebroadcast the entire demodu-
lated FM baseband spectrum. This includes the FM-multiplex
program signal along with any and all subcarriers that the sta-
tion might carry. With a clean, noise-free incoming carrier, this
Pass-Through method is generally preferred.
Regeneration
Advantages
However, there are advantages to ‘regenerating’ the composite
baseband signal. Regeneration refers to demodulating the in-
coming carrier down to left and right program audio and then
re-encoding the FM baseband using a separate stereo generator.
The stereo-gen can either be a standalone unit or one built into
the exciter.
Leading the regeneration advantages is a ‘clean-up’ of the in-
coming signal. ‘Ultrasonic’ noise (USN) above the program sub-
carrier compromises modulation efficiency, and regeneration
removes this source of noise. The AARON 650 has a variety of
Reception Tools that can prove very effective in reducing audi-
ble noise and preserving the quality of the program as it is re-
broadcast. RDS data can be regenerated as well, or replaced
with alternative housekeeping and messaging that may be more
pertinent in the rebroadcast signal coverage area.
The AARON 650 has the stereo regeneration capability built in,
one that can regenerate or completely replace the RDS data
subcarrier at the same time. The only disadvantage of stereo
regeneration is the slight time delay (latency) that is introduced,
but this is a very low figure in the AARON 650 specifications.
Switching Modes
Even using the factory-default settings, one can easily switch
between the Pass-Through and the Stereo-Regen modes. From
the Main Menu, navigate to Stereo Regen and push the knob.
Highlight the first menu
item, Regen On/Off and push
the knob. A pair of ‘radio
buttons’ will then allow you
to select either
On (Compo-