How to Connect
AUDIO OUTPUTS
Use the FIXED OUTPUT jacks to connect to a
conventional control preamplifier which has its
own volume control. The VOLUME CONTROL does
not affect the output of the tuner at the FIXED
OUTPUT jacks.
The output impedance at the FIXED OUTPUTS
is 600 ohms. Longer cables than are normally sup-
plied can be used to interconnect the MR 73 with
other equipment. The length of the cable is limited
by the capacity of the cable. The total capacity
must not exceed 1,000 pF. For instance: cables
with a capacity of 25 pF per foot may be 40 feet
long; 13.5 pF per foot cable may be 75 feet long.
Use the FRONT PANEL CONTROLLED jacks to
connect to a conventional control preamplifier
when use of the tuner volume control is desired.
These jacks may be used to connect to external
equipment such as power amplifiers or tape re-
corders where control of volume at the tuner is
necessary. The load impedance connected to the
FRONT PANEL CONTROLLED jacks should be not
less than 47,000 ohms. There is no difference in
the signal quality or maximum output levels avail-
able at each pair of output jacks.
CONNECTING AN FM ANTENNA
One of three antenna systems can be used: (1)
an outdoor FM antenna, or (2) a VHF-TV antenna,
or (3) the indoor dipole supplied with the MR 73.
An outdoor antenna is recommended for opti-
mum performance in all areas. In fringe (outlying)
areas, best results will be obtained with a highly
directional FM antenna used in conjunction with a
rotator. Rotate the antenna until the best reception
is obtained. Connect the 300 ohm antenna to the
FM ANT (red) terminals.
CONNECTING A 75 OHM ANTENNA
An unbalanced 75 ohm antenna can be con-
nected to the MR 73. A "type F" connector is used
to connect the 75 ohm coaxial cable to the back
panel FM ANT 75 input.
A VHF-TV antenna is often effective when it is
designed for both FM and TV reception. Connect
the two leads from the VHF-TV antenna to the
300 ANT (red) terminals.
CONNECTING AN INDOOR DIPOLE ANTENNA
The flexible folded dipole antenna (300 ohm) is
for use in urban or high strength signal areas.
Connect the two leads from the dipole to the
FM ANT (red) terminals. The flexibility of the thin
flat wire assembly permits it to be placed under a
rug, tacked behind the stereo . . . or, placed in any
other convenient location. In some cases, it may
be necessary to "position" the antenna for best
signal reception. This should be done before it is
permanently located.
Avoid locating the antenna next to other wires
or metal objects. This antenna may not prove
effective in houses having metal siding or metal
foil insulation.
AM BUILT-IN ANTENNA
For most local and moderately distant AM recep-
tion the built-in ferrite loopstick antenna may be
used. Set the AM ANT slide switch on the MR 73
back panel to the LOOP position.
AM OUTDOOR ANTENNA
For best long distance AM reception, use a cop-
per antenna wire 50 to 150 feet in length. Suspend
the wire in a straight line as high as possible. At-
tach the wire at each end with suitable glass or
ceramic insulators. Connect a lead-in wire at any
convenient point on the antenna. It is recom-
mended that a lightning arrester be used with an
outdoor AM antenna. The arrester should be well
grounded to a suitable water pipe or copper or
aluminum rod sunk into the ground.
Connect the lead-in wire to the AM ANT push
connector on the antenna terminal strip on the
back panel. Set the AM ANT Slide Switch to the
EXT position.
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