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4. SPEAKERS B
If the second pair of speakers is located near the first
pair and will be played simultaneously, then they must be
correctly phased with respect to the first pair as well as with
each other. But if the second pair of speakers is located
away from the first pair (in another room, for example) or will
not be played at the same time as the first pair, then their
phasing need not match that of the first pair. Of course, as
with any stereo speakers, the second pair still must be in
phase with each other.
_5, ANTENNA TERMINALS
In order to make connections to the four antenna
terminals, remove any connectors that may be fitted on
the antenna wires. Strip off 1 cm of insulation from each
wire, and in each conductor twist together the exposed
wire strands.
wire should be stretched out along the wall away from the
shelving and tacked in place.) You may wish to experiment
with the orientation of the AM antenna, in order to find the
position that provides the best reception of the stations you
listen to most often.
The short-wire antenna usually will provide satisfactory
reception of local AM broadcast stations. But if you wish to
improve reception of distant AM stations, attach a long-wire
outdoor antenna to the AM terminal.
As its name implies, a ~
"long-wire" antenna is a simple, straight wire whose length
may be anything from a few feet up to about 100 feet (30
meters), mounted parallel to the earth and as high as is
convenient. In some cases the effectiveness of a long-wire
antenna will be improved by connecting a second wire from
the Ground (G) terminal to a true earth-ground, i.e. a
copper-plated rod driven several feet into the earth. A
substitute electrical ground may also prove effective: a
cold-water pipe, a steam radiator, or the third hole of a
modern electrical wall socket.
FM Antennas. An antenna must be connected to the
tuner for effective reception of stereo FM broadcasts. A
ribbon-wire "folded dipole" antenna is included to get you
started. When you stretch out the ribbon-wire antenna you
will note that it is in the form of a T. The "crossbar" portion
of the T should be stretched out horizontally and tacked in
place—on a wall, on the back of a cabinet, or on the floor.
The "vertical" section of the T goes to the tuner's antenna
terminals. Connect its two wires to the two 300Q
input terminals.
In view of the exceptional sensitivity of NAD tuner
circuits, you may find that the ribbon-wire dipole antenna is
all you need for reception of strong local stations. But it is
not very efficient at rejecting "multipath" and other forms of
FM interference, and it cannot easily be rotated to optimize
its pickup pattern for best reception of stations in different
directions. Therefore, in most cases you should use a better
antenna. The recommended options, in order of increasing
cost, are as follows:
(1) A basic "rabbit-ears" indoor TV antenna without
auxiliary coils or tuning switches. Electrically, such an
antenna is just another dipole (similar to the ribbon-wire
antenna) with its tuned elements made of solid metal, but
with the advantage that it can be rotated. Stretch out each
of its two arms to a length of 307nches (75 cm), and orient
them horizontally or at a shallow angle less than 45 degrees
upward. The ribbon wire emegging from the antenna's base
should be connected to the-funer's two 300 terminals in
place of the supplied ribbon-wire antenna. Now, for each
station in turn, after you tune the station you can rotate the
antenna for best reception.
(2) A more elaborate rabbit-ears indoor TV antenna
with a tuning switch. This type of antenna does NOT have
greater sensitivity than the simpler rabbit-ears unit, so if your
problem is that the signals you want to receive are weak,
then an outdoor antenna is the only effective solution. But in
cities and in large buildings where signals are strong but are
contaminated by reflected "multipath" signals that interfere
with good reception, the tuning switch on an elaborate indoor
antenna may improve reception by reducing the interference.
(3) An electrically tuned indoor antenna. Again, such
antennas usually do not provide any advantage over the
simplest type of "rabbit-ears" unit for receiving weak signals.
But where strong signals are contaminated with interference,
the antenna's aiming and tuning controls can reject the
interference and yield cleaner reception.
(4) An outdoor antenna. Even the finest indoor antenna,
no matter how elaborate, cannot fully exploit the capabilities
of a good FM tuner. For the lowest noise, minimum distor-
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