McIntosh MR 77, Руководство пользователя

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to a stereo control preamplifier which has its own
master volume control.
The right hand pair of AUDIO OUTPUT jacks, pro-
vides FRONT PANEL CONTROLLED audio signal. The
program at these jacks is controlled by the MR 77 front
panel VOLUME control. Use these output jacks to con-
nect to external power amplifier, tape recorders, or
any equipment which requires continuous front panel
control of tuner output volume.
TUNING DIAL
The MR 77 has two dial scales:
1. FM —Marked 88 to 108 MHz
2. Logging s c a l e — M a r k e d 0 to 100
The logging scale can be used to accurately retune
any station. You may find it easier to keep a record of
your favorite stations by use of the logging scale.
A small portion of dial pointer has been illuminated
to increase the ease of tuning.
INDICATORS
There are four indicators on the MR 77 dial panel.
They are: STEREO indicator, MULTIPATH indicator,
SIGNAL STRENGTH meter, and the TUNING meter.
MULTIPATH INDICATOR
The MULTIPATH indicator is an exclusive Mclntosh
development.
The proper use of the MULTIPATH indicator makes
it possible to improve FM reception with precise FM
antenna positioning.
An electron ray indicator is used to show multipath
reception. It operates by movement of electron beams
inside a vacuum tube. When rotating the antenna, ob-
servation of the multipath indicator will show best
orientation for the FM station being received. Multipath
distortion causes the two beams on the indicator to
fluctuate rapidly. When the antenna is rotated to the
best position, the indicator beams tend to remain
steady. The directional antenna is then picking up only
the desired signal and rejecting the reflected multipath
signals. In some locations it is possible for the best
reception to occur when picking up a strong reflected
signal rather than the direct signal. Multipath distortion
is practically independent of signal strength.
STEREO INDICATOR
The STEREO indicator lights red when the dial
pointer is tuned to or crosses a station broadcasting
the 19 kHz carrier for stereo. The special circuit used
will light only when the 19 kHz multiplex carrier is
present in the signal. The indicator will not light on
noise pulses or interference.
SIGNAL STRENGTH METER
The SIGNAL STRENGTH meter indicates the strength
of the signal as received from the antenna. The higher
the indication, the stronger is the signal.
FM TUNING METER
An FM station is correctly tuned when the meter
needle is in the black area of the FM TUNING meter.
The action of the TUNING indicator is independent of
station signal strength.
MODE SELECTOR
Selects one of three operating conditions:
FM-MONO — In this position all broadcasts will be
heard monophonically. This position bypasses the
automatic stereo switching. The stereo indicator
will still light when a station is transmitting stereo,
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Front Panel Information