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A roof-mounted antenna has three fundamental ad-
vantages. First, its large size yields better sensitivity (pulling
in a stronger signal from the desired station) and a narrower
directional pattern for more effective rejection of multipath
reflections arriving from other directions. Second, its loca-
tion on a roof or tall mast places it above many sources of
interference—passing cars and buses, other buildings, etc.
Third, the strength of received FM signals is directly pro-
portional to the height.of any antenna above the ground.
The best choice is a directional FM-only antenna,
mounted as high above ground as is practical, and sepa-
rated by at least two meters (7 feet) from other antennas,
vertically and horizontally. If desired stations are located
in different directions (more than 90 degrees apart), the
antenna should be mounted.on a rotor for aiming. Brand
names of good FM antennas in the U.S. include Jerrold,
Finco, Wineguard, Antennacraft, and Archer (Radio Shack).
if you are using a 75-ohm coaxial antenna cable that
lacks a connector, you may attach its center conductor to
either 300Q antenna terminal and connect the cable shield to
the ground (G) antenna terminal. This unbalanced connec-
tion provides the required 75Q impedance for the cable. But
the 300Q antenna terminals are connected to the FM tuner
circuit through an internal "balun" transformer. The 75Q
coaxial socket is wired directly to the tuner circuit, bypassing
the balun transformer, so to obtain the best possible sensitiv-
ity, the coaxial cable should be connected to the 75Q socket.
If you install an outdoor antenna yourself, observe these
important CAUTIONS:
;
1. Do not mount the antenna close to electric power
lines. Plan the installation so that the antenna mast cannot
accidentally touch power lines, either while you are installing
it or later.
2. Include a lightning arrestor in the installation, to
protect both yourself and the tuner circuit from potential
danger during electrical storms.
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.
7. PHONO INPUT
Plug the signal cables from your turntable into these
jacks. If the cables or plugs are color-coded, refer to your
turntable's instruction manual to learn which cable or plug
is for the Left channel (upper jack) and which for the Right
(lower jack). Be careful to. insert each plug fully into the
socket so that the plug's metal skirt fits tightly over the
exterior of the socket. If necessary, crimp the plug's metal "
skirt slightly so as to obtain a tight fit with the socket.
8. VIDEO SOUND INPUT
Connect a video-related audio signal here, such as
the audio output from a video cassette recorder, video disc
player, TV monitor/receiver, or stereo television decoder.
Alternatively, any "line-level" audio signal may be con-
nected here, such as the playback from a spare tape deck.
9. CD INPUT
Connect the audio signal cables from a digital Compact
Disc player to these jacks. The input signal will be fed to the
Volume control before reaching any active circuitry, so the
amplifier's circuits cannot be overloaded by high-level sig-
nals from the digital player.
If you don't have a CD player, any other line-level signal
source (such as a spare tape deck) may be connected to the
CD input.
10. TAPE INPUT/OUTPUT
The tape connections may be used with recorders of all
types: cassette, open-reel, digital, HiFi VCR, etc. To make
recordings, connect a stereo patch cord from the amplifier's
TAPE OUT jacks to the recorder's audio LINE IN sockets
(not to its video or microphone inputs). To play back tapes,
connect a stereo patch cord from the recorder's audio LINE
QUT jacks to the amplifier's TAPE IN jacks.
The TAPE IN/OUT jacks may be used to connect a
signal processing accessory instead of a tape recorder. Ex-
amples of such accessories include a graphic equalizer, a
dynamic range processor, or an audio/video contro! center.
Connect a patch cord from the TAPE OUT jacks to the
processor's inputs, and another patch cord from the proces-
sor's outputs to the TAPE IN jacks.
Your tape deck may then be connected to the proces-
sor's own TAPE jacks.
11. SOFT CLIPPING
When an amplifier is overdriven beyond its specified
power output it normally produces "hard clipping" of the
signal with harsh distortion and power-supply buzz as the
output transistors saturate. The NAD Soft Clipping circuit
gently limits the output waveform and minimizes audible
distortion when the amplifier is overdriven. If your listening
involves moderate peak power levels, the Soft Clipping may
be left OFF. But we recommend that it be switched ON when
playing music at very high levels that might exceed the
amplifier's power capacity.
;
12. SPEAKER IMPEDANCE
The impedance of a loudspeaker varies with frequency,
and in many loudspeakers the impedance is lowest at the
frequencies where the highest power demands occur in
music. In many "8Q" loudspeakers this minimum impedance
is from 4 to 6 ohms, and in "4Q" speakers the minimum is
typically 3 ohms. If you connect two sets of speakers to the
amplifier, their combined impedance is approximately half
the impedance of either.
For these reasons, all NAD amplifiers and receivers are
designed to produce maximum power output into imped-
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