McIntosh MR 74, Руководство пользователя, Страница: 9 / 20

The action of the TUNING meter is independent of
station signal strength.
MODE SELECTOR
Selects any one of three sources:
AM— Connects the AM tuner section of the MR
74 to the output jacks.
FM— The FM position provides monophonic FM
or FM stereo at the left and right channel
audio output jacks automatically. With the
MODE SELECTOR in the FM position a
station broadcasting monophonic program
will be heard in mono. When the station
switches to stereo broadcast, the stereo in-
dicator will light and the MR 74 will auto-
matically switch to stereo operation. If mono
broadcasting is resumed the MR 74 will au-
tomatically switch to mono.
FM-MONO — Connects the FM tuner sections of
the MR 74 to the output jacks. This
position bypasses the automatic
stereo switching. The stereo indica-
tor will light when a station is trans-
mitting stereo, but all programs are
heard monophonically.
STEREO FILTER
The STEREO FILTER reduces noise on weak
stereo stations.
Position 1 reduces noise by approximately 10 dB.
Position 2 reduces noise by approximately 20 dB.
SELECTIVITY
In NORMAL, a very low distortion 10-pole filter
is connected to the IF system. Use this position of
the SELECTIVITY switch for normal reception con-
ditions.
In NARROW, a sharp 6-po!e filter is added to the
low-distortion 10-po!e filter. This yields a low-distor-
tion, highly selective 16-pole composite filter. Use
this switch position to reduce interference on distant
stations.
FM MUTING
Muting suppresses the background noise and hiss
normally heard between stations. Turn the control to
either LOCAL or DISTANT position for muting. Weak
stations that may not override noise and interference
are also suppressed by the muting. In the OUT posi-
tion, the muting is turned off to allow FM tuning with
the noise and interference present.
VOLUME
The VOLUME control has been precision tracked
throughout the listening range (0 to —65 dB) for ac-
curate stereo balance. It adjusts the output level at
the tuner FRONT PANEL CONTROLLED AUDIO OUT-
PUT jacks. The FIXED OUTPUT jacks are not af-
fected by the volume control.
The POWER ON/OFF switch is part of the VOL-
UME control. Turning the VOLUME control fully
counterclockwise turns the AC power to the MR 74
OFF.
PANLOC BUTTONS
At the bottom of the front panel corners are the
PANLOC buttons. After a tuner is installed on the
PANLOC brackets, pressing the PANLOC buttons
will lock the tuner firmly in position. Depressing the
PANLOC buttons will release the tuner. The tuner
can then be slid forward to the inspection and adjust-
ment position. The PANLOC system gives absolute
ease of installation, operation and maintenance.
SECONDARY CONTROLS
On the top of the chassis behind the front panel
is the DIAL SCALE INTENSITY switch. Adjust the
brightness of the dial lights by means of this switch.
Set the switch to BRIGHT for maximum dial light; set
the switch to DIM for subdued dial light.
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