User manual MCINTOSH MR65 SERVICE MANUAL

[. . . ] It offers the finest possible reception of FM monophonic and FM multiplex stereophonic broadcasts. Every desirable feature for your FM listening pleasure is included in the MR65 tuner. It is perfect for use in a stereo music system where nothing less than "THE Best" will do. Once you have enjoyed the outstanding performance of the MR65, you will understand why Mclntosh products have earned their reputation as "THE Best. " Your Mclntosh MR65 tuner will give you years of the finest possible FM reception, and will become a highly valued part of your home music system. TECHNICAL DESCRIPTION The MR65 tuner has a 6DS4 high-gain Nuvistor for the first RF amplifier. [. . . ] Using the previously drilled locating holes for correct alignment, carefully position the cutout template on the front panel. Scribe the rectangular cutout on the front panel and mark the positions of the six mounting holes. Drill the six 3/16 inch diameter mounting holes before cutting the panel opening. It is important that the cutout be just within the heavy black lines on the template. SHELF MOUNTING Locate the exact center of the proposed shelf area and scribe a line from the front to the back of the shelf. The SHELF CUTOUT TEMPLATE is marked for front panel thickness from ¼ inch to 1 inch. Fold the template on the line that corresponds to the thickness of the particular panel being used. Place the folded template on the shelf, butted against the back side of the front panel. Match the center line on the template to the scribed center line on the shelf. The shelf center line should also exactly meet the vertical center line used to make the front panel cutout. Mark the positions of the four ¼ inch diameter mounting holes. Use the 10-32 x ½ inch screws if the mounting shelf is 3/8 inch thickness or less. Use the 10-32 x 1 inch screws if the shelf is ¾ inch or 7/8inch thickness. Secure the chassis with the proper length 7 10-32 screws by inserting them up through the holes in the shelf, and into the threaded holes in the tuner chassis bottom. Tighten the 10-32 screws after you have first tightened the front panel screws. IMPORTANT Use of the wrong length 10-32 screws may cause electrical shorting in the tuner circuits. Attach the two metal panel end caps (packed with the tuner) on each end of the tuner panel by sliding onto the pins. (See Figure 10. ) The end caps are held by spring tension and can easily be removed if the tuner is to be taken out of the cabinet. MOUNTING IN THE L66 CABINET The Mclntosh L66 cabinet is supplied with complete instructions and all necessary hardware for installing the MR65 tuner. The Use the left hand pair of tuner AUDIO OUTPUT jacks for connecting to a conventional stereophonic control preamplifier. The output volume levels at these jacks are affected only by the tuner back panel dual concentric OUTPUT ADJ controls. The left hand pair of jacks is recommended when the tuner is used with a Mclntosh control preamplifier. [. . . ] If the meter pointer moves an appreciable amount on the first test, the second adjustment is necessary for precise meter operation. When the meter circuit is properly adjusted the meter pointer should stay centered in the black scale area when the AUTO FREQ CONTROL is turned from MIN to MAX. When the FM tuning meter is adjusted by this procedure, precise FM tuning is insured with the meter pointer centered in the black scale area. This procedure eliminates the possibility of noise affecting the meter adjustment. Adjust the brightness of the dial panel lights by means of the PANEL LIGHT switch on the tuner back panel. [. . . ]