User manual MCINTOSH MR55

[. . . ] INSTRUCTION MANUAL MclNTOSH MODEL MR-55 AM-FM TUNER (Serial No. 1KOOO and up) MclNTOSH LABORATORY, INC. 2 Chambers St. U. S. A. The Mclntosh MR-55 is a superior quality AM-FM Tuner for, use in home music systems and professional applications where distortion free reception is needed. Typical professional uses are "off the air" recording, broadcast monitor, rebroadcasting, etc. [. . . ] Solderless spade lugs are supplied for your convenience. --7-- 10' LOOP ANTENNA ANT. SWITCH IN THIS POSITION. LOOP AM ANT ANT PHONO INPUT OUTPUTS MULTIPLEX OUTPUT A. ANTENNA: Facilities are supplied on the MR-55 for the use of a low impedance loop antenna or a high impedance long wire antenna. AM reception will generally be improved through the use of a properly installed long wire outside antenna. For locations where an outside antenna is impossible or impractical a 10 foot loop antenna is supplied. The loop is attached between the terminals marked "HI" and "LO" on the "AM. ANT" terminating switch, located left of center next to the phono input jack on the back panel of the tuner, must be in the loop position. It should be mounted in as large a circle as practical in the vertical plane. --8-- An outside AM antenna is a wire as long as practical, mounted as high as possible above the ground, at right angles to power lines. The lead in should be carefully positioned away from all A. lines, The "ANTENNA" terminating switch must be in "ANT" position when using outside or long wire antenna. A good ground can be of assistance in AM reception. A good ground is described as a 1/2 inch rod 6 to 8 feet long driven into the earth. The ground wire is connected to the terminal marked "LO. " ANTENNA WIRE TO GROUND SUCH AS INSULATOR TO LONG W I R E AS HIGH ABOVE GROUND AS POSSIBLE 8' ROD IN EARTH. AM ANT. SWITCH IN THIS POSITION If the tuner is connected to an outside ground as described above do not connect any of the other equipment to the same ground to prevent ground loops. Ground loops can cause an increase in hum. For an alternate ground for use when using a long wire antenna connect the shorting link between terminals marked "LO" and "GND. " -9-- TO LONG WIRE ANTENNA. A N T . SWITCH IN THIS POSITION. LOOP AM ANT ANT PHONO INPUT OUTPUTS MULTIPLEX OUTPUT OUTPUT: Two pin jacks are supplied on the back panel marked "Output. " These jacks are in parallel. Interconnect between either of these jacks and the tuner input of your preamplifier by means of the 6 foot shielded cable supplied with your tuner. cable from the tuner into one of the auxiliary A. outlets on the back of the preampli- fier. cable from the amplifier can be plugged into the auxiliary A. outlet supplied on the back of the MR-55. [. . . ] SW. SIGNAL-SOURCE REMARKS ADJUST SIGNAL-OUTPUT AT SIGNAL GENERATOR Load T14 With 1. 5Kohm Resistance Load T13 With 1. 5Kohm Resistance FREQUENCY Front End to Local Oscillator T 1 3 : For Max. Antenna Terminals V. TV. M. --Crystal Probe C92: For Max. Oscillator Coupled to Antenna Terminals Thru 5 0 µ F Condenser Sensitivity Switch at Max. Pull Out V15 Point (K) ( P i n 7-V15) Broad C. W, Oscillator 600KC, 1500KC. Load C94 With 1. 5Kohm Resistance Load C92 With 1. 5Kohm Resistance IF-Strip and AVC TI6 > T4 T6 > > Upper and lower Slugs for Max. Point (L) (R34-C134) Antenna Switch at Ant. [. . . ]