Inovonics INOmini 402, Инструкция по установке и эксплуатации

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seconds this reverts to
Menu Screen 1, the main
screen, shown here as it
might appear when the
receiver is first powered-
up, but before it has been programmed.
Push the knob and
FREQ
will begin to blink. Now the receiv-
er may be tuned by turning the knob. A series of bars to
the right of
RF
show incoming signal strength.
Once the receiver is tuned, push the knob again.
FREQ
will
stop blinking and the tuned frequency will be fixed in the
receiver’s memory. This releases the jog wheel to navigate
to other menus.
Here is an example of a
tuned-in station that car-
ries RDS data. The sta-
tion frequency is shown
on the top line. The
RDS
notation indicates that RDS metadata is being sent along
with the music program and is being decoded by the 402.
The second line displays, the station’s PI code, the station’s
digital address. In the US and Canada station call letters are
decoded from the PI code and displayed here too.
RF
is a
rudimentary bargraph indication of incoming signal level.
Generally three or more
RF
bars will ensure a solid sign dis-
play. Text display response and stability will be limited in
large part by poor reception conditions. Even with several
RF
bars showing on the main screen, a high amount of FM
multipath distortion can garble the incoming RDS data.
Reception Metrics (Menu Screen 2)
Menu Screen 2 gives
quantitative measure-
ments of
RF
, the incom-
ing carrier level, and
MP
,
signal multipath distor-
tion. The attendant numerical values simply represent the
number of bargraph segments showing. This makes it easi-
er to keep track of the reading and whether it is going up or
down.
Ideally, the object is to orient your antenna to maximize the
top
RF
bargraph and minimize the bottom
MP
display. This
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applies whether you are waving around a random length of
wire, positioning a twin-lead dipole against a wall, or rotat-
ing an outdoor rooftop antenna. Multipath effects distort
the RDS data subcarrier, so it’s probably more important to
keep the
MP
bargraph as low as possible, even if that means
a little less
RF
at the same time.
Program Service Name (PS) (Menu Screen 3)
PS, the Program Service Name, is an 8-character RDS data
group that is displayed on the faceplate of every RDS-
equipped radio. Because this group is shown ‘no matter
what,’ most broadcasters put their “what’s playing” artist
and title information here.
Words here are generally
parsed to fit the 8-character limi-
tation. This means that small words like ‘
At
,’ ‘
To
,’
The
,’ or
‘
In
’ are combined with other short words. Large words are
broken in two. ‘Copacabana,’ for example, becomes
‘
Copacaba
’ followed by ‘
acabana
.’ Parsed word groups are
sequentially flashed on the display screen to spell-out the
entire message, and the message will repeat several times a
minute. What appears on
the lower line of Menu
Screen 3 is exactly what
shows on the faceplate of
the listener’s radio.
Radio Text (RT) (Menu Screen 4)
RDS Radio Text is a 64-character messaging group that may
be displayed on some consumer receivers but not on others.
Because this data is a scrolled (moving) message, many car
radios do not show Radio Text for safety considerations.
Some car radios may have a TEXT, a MESSAGE or an INFO
button that the listener must press to view Radio Text, and
then perhaps only when the car is not moving.
Some broadcasters use the Radio Text field for static mes-
sages, the station Web address, phone number or institu-
tional slogan, for example. Others will scroll the artist and
title info, program pro-
mos or advertising in this
group, as well as in the
PS field. Radio Text is
automatically scrolled in
Menu Screen 4.