Galvin-Mfg-Co（Motorola）-BR2RC 电路原理图.pdf

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1、VOLUME R-17, MOST-OFTEN-NEEDED 1957 RADIO SERVICING INFORMATION MOTOROLA RECORD CHANGER MODEL BR2RC PART NO 59D636270 stylus renewal (Service material below and on the next eight pages.) To renew a SO NO TONE stylus, gently lift tone arm and lift stylus retaining latch, then remove stylus and select

2、or bar as a single unit. When installing new stylus, be sure stylus rests in V. Replace with SO NOTONE No. N-2TS (Motorola Part No. 47K632185). OPERATING INSTRUCTIONS GENERAL INFORMATION This record changer will operate only on 117 volt 60 cycle AC. Loading. Lift the record control arm by holding it

3、 at at the far end (i. e., end furthest away from the center spindle) and then swing it clear of the records. Then, tak ing each record singly, place it on the center spindle rest ing the first record on the spindle ledge. Hold the record in position with the left hand and load the others with the r

4、ight hand in the same way. When all records are in posi tion, replace the record control arm over the center spin die. If the records are all of one diameter, it may be more convenient to group the ten together- see that the center holes are all in line and place the group on the center spin dle. St

5、arting Up. -Make sure that the pickup stylus is cor rect -that is, either 78 or 33-45 and similarly the speed knob. The Pickup is correctly set for 78 RPM records when knob at the front of the Pickup is sopositioned that the num ber 78 (Std) is upright. To position the Pickup for long- playing recor

6、ds, the numbers 33-45 (LP) must be upright. Then move the On/Off/Manual/Reject Knob to the left firm ly but not too roughly. That is all that is required. Rejecting. - -To reject a record, merely move the On/ Off/Manual/Reject Knob to the LEFT. When the last record is finished the machine will switc

7、h itself off automatically. Manual Operation. - -To play records singly on the rec ord changer, the following procedure should be adopted: Place desired record on the turntable manually and replace control arm in its operating position. Turn On/Off/Manual/ Reject switch to the Manual,r position only

8、. The turntable will now revolve at the selected speed. Lift the Pickup off its rest and place in position on record. The record will now play and when completed the Pickup will return to rest and the unit will switch off automatically in the normal man ner. To Remove the Records. - -Lift the record

9、 control arm and turn it out of the way. Grasp the records together and lift them gently from the center spindle, easing them past the ledge on the spindle. After loading always see that the Magidisk Record Se lector Arm (Item 8M139) is out and not stuck in a vertical position. In other words, it mu

10、st be BELOW the records. This record changer is designed to play all of the exist- ing types of phonograph records in common use. First, there is the record that rotates at a speed of 78 revolutions per minute. This type has been in common use for many years. Generally, this record is produced in tw

11、o diameters, 10* and 12, playing respectively about 3-1/2 and 5 min utes per side. This record changer will play a total of ten records of average thickness at one loading, and the dif- ferentdiameters can be mixed; the machine itself will select the correct conditions for each diameter WITHOUT any

12、ad justment. The only manual adjustment necessary is to turn the Pickup to the 78 position and rotate the speed control knob to the 78 position. Secondly, there is the record that rotates at 33-1/3 revolutions per minute. This is commonly called the LP or long -playing type. It is generally produced

13、 in two diam eters12“ and 10. The playing time is much longer per side than with the old 78 RPM type. Thus, one side of the 12 diameter can play up to 20 minutes. Again this record changer will accept a mixed loading of the different diam eters and will automatically select the correct conditions fo

14、r each. Again the only manual adjustments are the Pick up to the 33-1/3 position and the speed changer knob also to the 33-1/3 position. Thirdly, there is the record that rotates at 45 revolu tions per minute. This is only produced in the 7 diameter size. Some of these records are sold with a large

15、center hole which must have an adaptor plate fitted to reduce the hole size to the common standard to fit the center spindle. The more recent tendency is to sell 45 RPM records with the standard small hole, allowing this center to be pushed out when the large hole is required. With these records the

16、 speed must be stet to the 45 position and the Pickup set to the 33-1/3 position. Fourthly, there is the record that rotates at 16-2/3 revolutions per minute. This is, at present, only produced in the 7 diameter size. Generally speaking, it is advis able to play these records singly. Some of these r

17、ecords are manufactured with a very large center hole. In such cases, they are sold with a special cardboard adaptor which reduces this hole to the standard size for normal use. Many records are, however, manufactured with the small stand ard center hole. With these records, set speed change knob to

18、 the 16-2/3 position and the Pickup to the 33-l/3 posi tion. 78 收音机爱 好者资料库 RadioFans.CN VOLUME R-17, MOST-OFTEN-NEEDED 1957 RADIO SERVICING INFORMATION MOTOROLA Record Changer Model BR2RC Service Material, Continued LUBRICATION A periodic check should be made to insure that your changer is lubricate

19、d adequately at the points detailed below: Heavy grease should be used on the following points: (a) Main slide (Item 8MI62), grease faces rubbed by cam (8M168), and also end of tongue. (b) Actuating lever (8M152), grease inside face of pawl re setting strip. (c) Reset arm (8M204), grease portion tha

20、t rubs on cam gear (8MI60). (d) Main sub-plate (8M169) grease guide slots. (e) Ballrace (8M68), fill ballrace cup with grease and as semble with open end upwards. (f) Four speed pawl (8M52), grease nose of pawl. (g) Speed change slide (8M44), grease location steps. Light oil should be used on the fo

21、llowing points: (a) Control spindle (8M4), oil spindle. (b) T. T. Bearing (8M63 and 8M65). (c) Rivet (8M135), oil sparingly taking care not to drip oil down on to plastic selector arm bearing (8M138). (d) Rivet (8M1I6). (e) Jockey pulley bearing (8M33). (f) Speed change slide (8M44), oil portion of

22、mainplate over which slide moves. PLEASE NOTE No oil should be used on the Magidisk Record Se lector Bearing (see Figure 7). ADJUSTMENTS Needle Set-Down. - -The set-down position of the needle on the record is adjusted by manipulation of the needle ad justing screw (Item 8M261). (See Figure 4.) Adju

23、st this screwuntil the correct set-down of the needle on a 10 rec ord is obtained. The correct position is l/8 from the edge of the record. It is advisable to make this adjustment with a stack of 10 records on the turntable. When correctly positioned for a 10 record, the 12 and 7 needle set-down wil

24、l also be correct. Pickup Arm Height. - -The pickup arm height is adjusted by the pickup height adjusting screw (Item 8M257). (See Figure 4.) To raise the height of the pickup arm, turn this screw counterclockwise. To lower the pickup arm turn clockwise. The pickup height should be adjusted so that

25、with a stack of ten average thickness records on the turn table, the point of the needle clears the top record by 1/16 inch. A check should then be made to insure that the pickup arm clears the underside of records loaded on the center spindle. Needle Pressure.-Adjustments may be made by re position

26、ing the pickup balance spring (Item 8M263) in the various adjusting holes provided (see Figure 4) until the correct pressure is obtained. Adjusting of Speed Change. - (1) Set the four speed knob at the 16-2/3 RPM position. (2) Slacken setscrews on the 4-speed pulley (Item 8M94) and adjust until the

27、jockeypulley (Item 8M32) is en gaged on the smallest pulley diameter just clear of the top step (see Figure 2). (3) Tighten setscrews. DISMANTLING (1) Turntable Assembly (Item 8M62A) Remove circlip (Item8M109) and lift the turntable vertically upwards over the center spindle. Take care, not to lose

28、the thin thrust washer (that sticks to underside of turntable boss), ballrace of second thrust washer. NOTE: Before replacing assembly, set speed knob to 45 RPM. This al lows easy maneuverability of jockey pulley when replacing turntable, without possible danger of bending jockey arm. (2) To Remove

29、Control Arm Assembly (Item 8M2A) (See Figure 7) Remove pin (Item 8M5) on underside of control arm spindle (Item 8M4) (See Figure 3). (3) Pickup Arm Assembly This must be done after the changer has switched itself off. Unsolder the pickup leads from the connecting tagstrip. Un screw the pickup top be

30、aring (see Figure 4) and then lift the pickup arm clear. Replace the pickup top bearing to avoid losing the spacer washer. (4) Main Sub-Assembly Remove turntable and pickup arm as described and 3 screws (Items 8M114, 8M115 and 8M190) holding subunit. Main sub-assembly can then be gently removed from

31、 unit-plate. (5) Sonotone 2TS Cartridge (from pickup arm) Unscrew the two self-tapping screws securing the cartridge bracket to the arm moulding. Ease the two pickup lead tags from the lugs at the rear of the cartridge case. TROUBLE SHOOTING CHART SYMPTOMS Turntable does not rotate when On/Off/Rejec

32、t Knob is turned to ON* (1) No current to motor (2) Motor defective (3) Jockey pulley not engaging turntable rim. (a) Check that current has reached record changer motor. (b) Check that switch box assembly is functioning cor rectly. (c) Check all wiring and solder terminals to and from the switch bo

33、x assembly (see Figure 1). (a) Remove the turntable and allow the motor to operate without load. If motor spindle is not rotating and voltage is reaching the motor, the motor is faulty. Repair or replace. (b) Check that the 4-speed pulley (Figure 2) is not loose on motor spindle. If loose adjust as

34、under Adjustments of Speed Change (a) Check that the jockey pulley is free to pivot. (b) Check that the jockey pulley spring is correctly po sitioned (see Figure 2). 79 收音机爱 好者资料库 RadioFans.CN VOLUME R-17, MOST-OFTEN-NEEDED 1957 RADIO SERVICING INFORMATION MOTOROLA Record Changer Model BR2RC Service

35、 Material, Continued SYMPTOMS TROUBLE CHART - Contd REMEDY (c) Carefully clean the inside rim of turntable and rub ber tire on jockey pulley to insure that they are free from oil and grit. Turntable revolves when (1) Incorrect manipulation of Insure that the On/Off/Reject knob is turned to its full-

36、 On/Off/Reject Knob is control. est extremity in the ON direction. This does not up turned to ON but pick- ply when operating the changer manually, up remains stationary on its rest. Pickup lifts but fails to move in when record drops. The pickup returns to rest and the turntable continues to revolv

37、e (1) Stop pin (Item 8M199)(see Figure 3) not dropping freely. (2) Adjusting link (Item BM20B) too tight (see Figure 3). (3) Stiffness in stop bracket as sembly bearing (see Fig- Remove all grease, oil, grit, burrs or rust carefully from the stop pin and spring (Item BM201) and insure that spring is

38、 not damaged. Slacken adjusting link by decreasing bend. Free and lightly oil. JOCKEY ARM ASS Y. 4-SPEED PULLEY JOCKEY PULLEY ASS Y JOCKEY PULLEY SPRING. FIGURE 1. GRUB SCREWS FOR ADJUSTING HEIGHT OF PULLEY STOP PIN RESET ARM SPRING MOUNTING SPRING ADJUSTING LINK STOP PAWL SPRING PIN CONTROL SPINDLE

39、) CONTROL SPINOLE SLEEVE n - STOP LEVER BEARING TWrft. II STOP BRACKET 0 ass t MOUNTING SPRING STOP LIVER ASS Y V TRANSIT SCREW WASHER fk A CIRCLIP CUT OFF ARM SPRING FIGURE 3. 80 收音机爱 好者资料库 RadioFans.CN VOLUME R-17, MOST-OFTEN-NEEDED 1957 RADIO SERVICING INFORMATION TROUBLE CHART - Cont*d SYMPTOMS

40、CAUSE REMEDY IV. Pickup lifts but fails to move in when record drops. Pickup returns to rest and changer switches off. (1) Cut off arm (Item 8M228) (see Figure 3) not return ing to neutral position, (2) Undue friction at stop lever assembly bearing (see Fig ure 3) (3) Stiffness in stop bracket as se

41、mbly bearing (see Fig ure 3) (a) Cut off arm spring (Item 8M227) (see Figure 3) damaged. Replace. (b) Friction on moving surfaces of cut off arm. This lever must be absolutely free to slide in its slots. Check for rust, frays in slots, etc. Remove, clean and lightly oil. Free and lightly oil. V. Pic

42、kup arm strikes rec ord on spindle when it rises or needle catches on last record when it moves out. (1) Pickup arm height not ad justed properly. (2) Control arm (Item 8M2) not holding records level. (3) Needle bent in crystal cartridge See instructions for Adjusting Pickup Arm Height under Adjustm

43、ent. Hold control column securely and twist control arm un til it will hold record stack parallel to top of turntable (see Figure 3). Replace needle, (See necessary instructions under Dismantling.) VI. Turntable speed too slow. (1) Tightness in motor bearing. (2) Binding in turntable bearing. (3) Jo

44、ckey pulley slip. (4) Input voltage too low (5) Operating temperature too low. (6) Undersized 4-speed pulley Tap lightly the side of motor laminations to free self aligning bearings. Check turntable bearing for freedom. If it does not turn easily when disengaged from the jockey pulley assembly (Item

45、 8M32A) remove turntable, clean off foreign matter and lubricate with light mineral oil. Remove turntable and clean rim of jockey pulley. Oil jockey unit joints and pivots and make sure all move freely. Remove any trace of oil on jockey pulley rub ber or inside of turntable rim. The input voltage sh

46、ould be not less than 100 volts. If the machine has been standing in a cold place or op erated in surroundings at a temperature of less than 45F. the turntable speed may be too slow initially. Remove turntable and fit new 4-speed pulley. Pulleys are available as follows: Small-red pulley: Medium- gr

47、een pulley; Large-blue pulley. To increase turntable speed remove existing pulley from the motor shaft and fit the next size larger, or vice versa to reduce speed. When fitting new 4-speed pulley see Adjustments of Speed Change under Adjustments. VII. Turntable speed too fast. (1) Input voltage too

48、high, (2) Oversize 4-speed pulley. Replace 4-speed pulley as instructed at 6 under Turntable Speed Too Slow VIII. Changer continues to cycle. With pickup dropping on to record during every cycle. (1) Pawl reset strip (see Fig ure 5) distorted. (2) Actuating pawl and friction link assembly (see Figur

49、e 5) ; too free. Make sure that this strip is straight and resets friction link (Item 8M154) and actuating pawl (Item 8M156) by engaging with friction link shoulder during cycie (see Figure 5). Damp down the bearings of this assembly by smearing with medium grease. IX. Noise during playing of (1) Motor rumble. If a low pitched rumbling sound come a from the loud- record. speaker while the record is being played, check the motor rubber mountings to be sure the motor is