Operation Manual

shielded 300-ohm cable. (An unshielded lead-in
wire can act as an omnidirectional antenna, and
can cancel the directional benefits of your
antenna.) Low-loss 300-ohm shielded cable consists
of two inner conductors plus an outer shield and
insulating jacket. This type of shielded cable
effectively prevents the lead-in from contributing
multipath distortion.
For rural areas, it is recommended that a local
dealer be consulted about antenna installation and
lightning arrestor protection. Master antenna
system are not recommended for use with your
Model 2230; such systems are usually designed
expressly for television reception and frequently
suppress FM signals before distribution. In
addition, master antenna systems often severely
limit good quality FM reception.
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FM ANTENNA
FM ANTENNA
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FM ANTENNA
SINGLE WIRE
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AM ANTENNA
Where outdoor antennas are proh ibited or
inconvenient, use a simple form of 300-ohm, TV
"rabbit ear" antenna or the simple ribbon-type
folded dipole antenna supplied with the Model
2230. Both are practical and will give satisfactory
results in primary signal areas. Your Model 2230
Receiver will accept either a 75-ohm or 300-ohm
antenna. (See diagram Figure 3.) The 30().ohm
antenna cable should be connected to the two
terminals marked FM on the ANTENNA terminal.
When using 75-ohm coaxial antenna cable, connect
its shield to the "G" (GROUND) terminal, and its
inner or center conductor to either of the FM
terminals.
(Note: Close inspection of standard zipcord will
reveal some form of coding on the insulation, e.g.,
ridge or groove on one edge, one of the wires may
be "silver" while the other is bare copper.) Coded
wires help insure identical connections for each
channel.
For each channel, the coded wire can be connected
between the "common" terminal of your
loudspeaker and the GROUND terminal of the
amplifier channel. The remaining uncoded wire is
then connected between the remaining loudspeaker
and amplifier terminals. This insures correct
polarity or phasing of identical loudspeakers.
If there is any doubt about phasing of loudspeaker
pairs, or if they are not identical loudspeakers, a
simple listening test can verify correct phasing.
With program signals fed to both channels, and
with the MONO pushswitch depressed, the sound
should appear to originate at a point midway
between the loudspeakers, with the balance control
centered. As the balance control is turned away
from the center position, the sound source should
appear to move toward one of the loudspeakers.
Room acoustics can sometimes make this test
ambiguous or confusing. If so, temporarily move
the loudspeakers asclose together as possible. Then
set the controls for balanced MONO operation and
listen to program material with strong bass pass-
ages. Reverse the wires to one of the loudspeakers
and Iisten to the same passageagain. If there is
noticeably less basswith this reversed connection,
change the connections back to the original ar-
rangement. If there is noticeably more bass, leave
the wires connected in reverse.
These phasing procedures should be used with each
stereo pair of loudspeakers, whether MAIN or
REMOTE. If both pairs of loudspeakers are used in
the same listening area, ensure that the MAIN
pair is also "in phase" with the REMOTE pair.
CAUTION:
NEVER DIRECTLY CONNECT THE lOUD-
SPEAKER TERMINALS OF ONE CHANNEL
IN PARAllEL WITH THOSE OF ANY
OTHER. ANY RESULTING DAMAGE IS
NOT COVERED UNDER WARRANTY.
Figure 3. FM/AM Antenna Connection
FM ANTENNA
The best FM reception is obtained with a
Log-Periodic type antenna, mounted on a good
quality rotor system. For fringe areas, Marantz
recommends a Log-Periodic antenna with six or
more elements designed expressly for FM
reception. For minimum local noise and multipath
pickup by the lead-in wires, use a balanced and
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3000 SHIELDE~SHIELO
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