Thorens Inc. CD-40 Schematic

Thorens Inc. CD-40

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Product Information:
Manufacturer:Thorens Inc.

Schematics Content

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I. Adjustment of pick-up
1. The pick-up lands too much outside or inside at the beginning of an audition: a) too much outside:
Turn the screw No 1 very gently in a clockwise direction. This screw can be reached through the hole No 2 of the unit plate when the pick-up is placed on the first groove of a in " record. b) Too much inside:
Turn the screw No very slightly in a counter clockwise direction.

2. The pick-up remains on the edge of a record:
This only happens when recorde have no running in groove. a) Verify that the Record Changer is mounted in a perfectly horizontal position.
This can be adjusted by means of the suspension screws and nuts of the unit plate. b) The small spring No 3 should be slightly bent towards the interior of the aperture No
3. The pick-up lands too much inside but only for the first records:
a) Verify if the record changer is perfectly horizontal.
b) The spring N0 3 should be slightly bent towards the outside of the aperture No 4
4. The pick-up does not rise enough to play the last record of the pile:
Bend slightly upwards the steel wire No 43 situated under the pick-up arm. The normal adjustment is reached when a medium needle touches the velvet of the turntable.
5. The pick-up lands and rises up immediately without playing a record:
aj Verify that the lever No 5 turns perfectly free on its pivot, so that it is very vigorously brought into position by its spring No
6. If this is not the case, clean the friction surfaces. b) If this is insufficient, bend slightly upwards the arm No 7 of lever No 5 (hidden beneath the mounting plate) by means of a screw-driver. The arm is accessible through the hole No 8
6. The pick-up rises up before the end of a record:
a) This irregularity is due to the hole in the record being out of centre in relation to the grooves, or the hole is too large. Such records are not suitable for record changers. b) If the auto-trip mechanism is considered too sensitive, bend slightly the free end of the trip lever No 9 in a clockwise direction.

7. The pick-up does not operate immediately before being dropped on a recond:

a) The tension of the flat spring No in should be slightly increased so that it leana more on the cam. b) The spiral spring No 46 (fig. I) should be reinforced.

8. The pick-up remains on the record at the end of an addition:
The record feeding mechanism is actioned by the auto-trip mechanism. If, at the end of an audition, the mechanism does not operate, i. c. the pick-up remains in the last groove, proceed as follows: a) Verify if the record in question has a running-off groove. Only records with a running-off groove can be played automatically on a record changer. b) Action the " reject " button: lat case: The automatic cycle mechanism starte:
Remove the turntable and examine the leather of the striker No ll. If this is worn, give it half a turn to present a new surface to the auto-trip lever No 9 or replace it by a new one. If this leather is in good condition, then increase the tension of the friction spring by turning the adjusting screw No 12 about half a turn in a counter-clockwise direction. 2nd case: The automatic cycle mechanism does not start:
This means that the record changer is blocked owing to the hardening of the grease on the came, the presence of an erratic particle, or an important distortion of one of the organs. Clean the cams and gears and control the whole mechanism.
9. The 12 " records rub the pick-up arm when dropping from the record spindle: Verify the record feeding mechanism according to $ II, 1 a) and b). Adjust accordingly.

II. Record feeding mechanism
1. Records fail to drop from the record spindle:

a) Examine the thickness at the centre of the record. The standard thickness is between 1,5 and 2,6 mm. Thinner or thicker records do not drop correctly from the spindle. A too thin record can be played alone or on the top of the pile.

b) The correct adjustment of the pueh-lever No 45 of the record'spindle Ne 44 is shown on fig. II. For this control, turn slowly the record changer turntable until the push lever is out at its maximum point. If the dimension of 6,9 mm is not reached, give half a turn to the bolt No 13 in a clockwise direction after having onscrewed But No 14. If the dimension of 7,1 mm ie exceeded, turn in the opposite direction bolt No 13.

2. Two records drop together from the record spindle:
in such a case, these two records are too thin at the centre or out of shape.

3. The record central bole enlarges or splits:
This only happens when the records are too thin at the centre.

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III. Turntable brake, auto switch and pause
1. The record changer does not stop after the last record:
a) Verify if the lever No 15 is free in the loop No 16. If such is not the case,
adjust this lever until it is perfectly free to move. b } If the trouble does not come from this, verify when there are no records on the platforma No 26 if the lever No 15 abuts against the feeler No 17. If this is not the case, lengthen the lever No 15 by loosening the regulating screws. c) The irregularity may also come from an erroneous oiling of the feelers 17 and 18. Remove the oil with benzine by means of a brush.

2. The starting button does not remain on start
a) The lever No 15. is engaged on the extremity of the feeler Ny 17, disengage and adjust. hi The lever No is on which is the leather of the turntable stop strikes against the edge of the hole No 19. Adjust.

3. The last record cannot be repeated, the record changer stops:

Bend slightly the small tongue No 20 by means of a werew-driver in the blot No 21.

4. The pause lasts indefinitely:
Examine firstly if the pause epring No 22 is broken. In such a case proceed as follows: a) Remove the motor by unscrewing nute No 23, place the pause button on
" pause " and turn the large toothed wheels until the pause spring is quite visible. Remove the fixing screw No 24, the broken pause spring can then be removed and replaced. b) If the pause spring is intact, the extremity of this spring should be slightly bent towards the outside of the large toothed wheel so that this extremity meshes more effectively to the star No 25. c) If that is not sufficient, increase the pressure of the Hat spring No in against the cam.

IV. Selecting mechanism for in " and 12 " records When the pick-up does not land into a position corresponding to the diameter of the record placed on the turntable (this record should have previously fallen from the platform No 26 and have actioned the feelers No. 17 and 18) proceed as follows:

a) Verify the mechanism of the record feeding following $ II, 1 a) and b).

b) If the irregularity does not arise from a faulty adjustment of the record feeding mechanism, examine if the unit plate of the apparatus has been bent by a shock in the angle of the platform No 26. Should such be the case, carefully adjust the unit plate. c) Verify if the lever in the form of U No 27 does not touch the mounting board.
The aperture of this mounting board should be executed following the template supplied with each apparatus. d) Verify that the elbowed lever No 28 is not bent or twisted, it should be perfectly free in its two articulations, c) The lever in the form of U No 27 should not contact the lever No 28, but must be free to follow the motion of feeler No is when a 12 " record descends on the record spindle. f) The fceler No is should be perfectly free at the time when the feeding mecha.
nism is in action. This feeler should not be oiled. u If all the preceding points are in order, increase the tension of the friction spring No 29, by nicans of the blocking nuts No 30. h) The position of the abutment in " - 12 " No 31 can be adjusted means of the two screws No 32 if its position does not correspond to the diameter of the record descending the spindle (only modify this adjustment if all the preceding points are in order).

1. The speed varies during the reproduction of certain records:

a) Control these records. Records that are not flat slip over each other and thus do not correctly follow the movement of the motor.
If this difficulty does not come from the records, verify the points
2., b) and
2. The motor does not start when the button is placed on Start

a) The motor can only start by itself when the pick-up is on a record or if at rest outside the turntable. When the turntable is not stopped with sufficient force, the mechanism overruns the normal rest position and the motor does not start. Change the position of the leather No is to present a new surface,
or renew. b) The record spindle No 44 should be perfectly free in the hole N � � 46 of the centre shaft. Control carefully this point when in the normal playing pouition.
This hole should be oiled from time to time. c) Verify the lubrication of the motor following $ A. d) The stater received a shock that put it out of centre, adjust accordingly,

3. The motor stops suddenly and remains blocked:

Verify firetly if it is really the motor that is blocked and not the record changer mechanism. The stoppage of the motor is often due to the friction of the principal bearing owing to lack of oil in the hole No 33. It may be necessary to dismantle the motor (see & B & C) to liberate the bearing.

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Fig. III

Fig. IV

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4. The motor is noisy (hissing):
a) Verify the point
2. b). b) The axial abutment ball No. 34 situated at the extremity of the rotor is worn also the steel plate No 35 placed in the abutr'ont No 36 fixed to the motor casing. Dismantle the motor as shown under B & C and replace the ball and metal plate. At the same time insert a small tube No 37 furnished by the factory if not already supplied (see diagram No V). The tube should be filled with vaseline or a graphite lubricant. Remark: If the worn ball cannot be removed from the rotor with a magnet, it should be slightly ground and then removed with an awl. Do not grind the axle of the rotor.
5. The motor runs by fits and starts:
The motor should be dismantled following & B. Remove the top motor plate No 38 by unscrewing the 3 screws. Verify if the fibre wheel is faulty (broken teeth). The centre shaft with the fibre wheel will be replaced by the factory.
Lubricate before mounting the new shaft. A. Lubrication of the motor:
The motor should be regularly lubricated generally after 100 hours use. To do this remove the turntable and introduce a few drops of good quality thin oil into the lubricating holes (coloured red), by means of an oil-can or a needle. Do not use consistent oil. B. Dismantling of the motor from the unit plate of the record changer:
Remove the toothed wheel with the striker No 11 by a simple pull. Loosen the 3 nuts No 23 also the screw No 39 of the speed regulator lever. C. Dismantling the motor:
Unscrew the 4 fixing screws of the stater. Remove the entire block formed by the housing No 41 and the stater No 42. To reach the commutator and the abutment, remove very carefully the housing, leaving the block of the commutator with the stater. Press against the commutator by the medium of the terminals to make it slide by pressure, out of the housing, which should be withdrawn at the same time.

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Dimensions The upit plate is 15 in. (380 mm.) by 12 in. (300 mm.) wide. It requires a clear. ance of 16 / 2 in. (420 mm.) X 14 in. (350 mm.) surface, 6 in. (150 mm.) above the unit plate, 3/4 in. (80 mm.) bolow the unit plate. Minimum height required for placing the pile of records into position before the audition: 71/2 in. (190 mm.) above the unit plate.

The motor is fixed rigidly to the record unit. This prevents any interference with the pick-up and eliminates all vibrations. The Record Changer " Concert " is equipped with one of the following types:

1. AC motor. The AC motor is of the induction type entirely encased. Its high palling capacity ensures perfect functioning of the changer mechanism and its silent operation as well as its patent regulator contribute to give a faultless reproduction of your records. It causes no interference on the pick-up and the heating is reduced to minimum.

2. DC motor. The universal motor for AC and PC current presents, with. particularly high pulling capacity, the same characteristics of regularity and silence.
Commutator for adaptation to the following voltages:

Consumption: in watu maximum.
Caution | The universal motor must be connected to the earth as shown on the connection plan supplied with each record changer, otherwise noise will develop.

Tho turntable speed is normally set at 78 r.p.m. It can be varied by means of the indicator lover.

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Pick-up The Concert " record changer is equipped with the new highest precision Thorens pick-ups " Rondo " Gavotte " Fugue Special " or Crystal Special types which guarantee the beat audition and the minimum wear of your records.

RONDO good quality pick-up of electromagnetic type with high impedance in arm made of stamped metal, light and rigid, which can be connected directly to radio receivers. Minimum impedance required for this connection: 50,000 ohms.

GAVOTTE a high-class pick-up of electromagnetic type with low impedance elno in arm of stamped metal which must be connected to the radio receiver by the medium of ite coupling transformer. Minimum impedance for this connection: 200,000 ohm. "

FUGUE SPECIAL a professional type pick-up, electro-dynamic with low impedance, also in arm made of stamped steel. This pick-up must be connected to the radio receiver by means of its coupling transformer. Minimum impedance for this connection: 0,5 megohms.

CRYSTAL SPECIAL a high quality piezo-electric pick-up light and flexible which can be connected directly to the radio-recover. Minimum impedance for this connection: 0,5 megohms.

These four models play with interchangeable needles.
When fixing the coupling transformer to the cabinet, ace that a sufficient distance is left in relation to the motor (8 in. 20 cm. minimum).
NOTE: Detailed technical characteristics of the above mentioned pick-ups are described in special leaflet.

Installation To ensure a perfect functioning of the record changer it is very important that the installation and mounting should be made in a correct manner.
A template is supplied with each apparatus. The aperture to be made in the mounting board must be executed with precision as also the drilling of the fixation holder so as to give the mechanism the Decorary freedom and to obtain perfect ope. ration. Any effort to force or any torsion exercised on the unit plate may provoke a faulty functioning.
The mounting on springs, following the mounting diagram, eliminates this risk and ensures flexible and floating suspension of the unit plate. This prorenta any interference with the pick-up and loud-speaker and eliminates all vibrations.
REMARK: If in the case of a very vopsitive amplifier the hum level in coppi dered too high, the apparatus should be mounted rigidly on the mounting plate. To avoid any flexion of the unit plate, it could be made rigid by means of mutable washers. If the interferences with loudspeaker'do occur, this latter should be mounted on springs. Adaptation to the tension of mains For both types of motors the commutator pertaining instantaneous adaptation to voltage of maing is placed under the turntable. After, having removed the turatable, turn the commutator screw by morns of a screwdriver until the slot correspond with the desired voltage.

CAUTION, Do not proceed with any connecting or adjustment to the record changer before disconnecting mains current.
Maintenance Motor and record changer mechanism Motor and mechanism only need lubricating from time to time, generally after 100 to 150 hours use. To do this remove the turntable and introduce a few drops of good quality thin oil into the lubricating holes (coloured red). Do not use consistent oil which might block the motor. After a few years use it would be advisable to replace the burdened grouse of the came, gear and other rubbing surfaces by fresh and clean grease.
Do not oil the selecting feelers.

Record spindle Apart from cleaning the push-lever periodically, it is necessary when oiling the motor to introduce also a drop of oil into the hole of turntable spindle where the record spindle pivots.

The pick-up being high precision instrument, say repair should be mudo through the competent services of Thorens Agencies.

Operating instructions
The " Concert record changer CD 40 will play. maximum of top in in. records or eight in in. and 12 in, mixed in any order. To operate, proceed in the following manner:

1. Raise overarm, place record spindle in position cod place the records on the spindle shoulder. Tho lowest record of the pile will be played firu.
2. Turn the record spindle on which the records are placed so that the lower edge of the pile of record, rents on the platform, Lower the overarm, the bole in the free end then holds the top of record spindle into position in the direction of be platform. Make sure that the overarm is completely lowered on to the record spindle.
3. Insert needle in pick-up either: upper noodle for record changers fitted with " GAVOTTE " FUGUE " and " CRYSTAL " pick-ups oply, or a verol-permanent type needle that will play in or more record.
(reverse pick up head to do this). + Move No. 2 knob to the position " start From this moment, the changer functions automatically until all the records are played and at the end of last record it will stop automatically.
Any record aot required to be played may be automatic'ally rejected by moving knob No. I to position " reject . The following record is then brought into playing position.
When the knob No. 3 is placed on position " repost " the record being played will be repeated once more - Room as the pick-up has reached the final groove.
A part only of record can be repeated If knob No. 3 being on position " repeat knob No. 1 in moved to position " reject
A pause of 2'12 minutes duration can be introduced between two record. by placiox knob No. 4 on position Pause ".
The audition can be resumed at any moment by moy. ing knob to itn initial position.
The record changer can be stopped by moving knob No. 2 to position stop ". It will start again if the knob is placed on position start resuming playing at the place where it was interrupted.

Do not force the button into position when it resiste. It can always be set plot as soon as the record changing mechanism operates.

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Important remarks Placing records on record spindle Do not place roughly the pile of records on the record spindle. This risks to deteriorate their central holes. Pick-up changing mechanism The movements of the pick-up are accioned by the record changer mechanism. The pick-up should therefore'never on any account be forced into position by hand. The overarm should not be raised from the record spindle while playing to avoid risk of deteriorating the recorde. Record spindle It is essential that the record spindle should fit perfectly free in the hole of the toro table spindle when the overarm in in playing position. This bole should be kept quite clean. Records The " Concert " record changer provides for standardized records in thickness and diameter. If a thinner record or one deteriorated at the centre in employed, it may happen that it will not drop from the record spindle, and cause it to lift up. Io such a came it will mattice to change the position of the record in the reserve pile in order to ensure a normal feeding.
It may happen that new records have a slight burr around the centre hole; this burr may provoke jamming of the push-lever thun bindering the release of the records, To avoid tbis, cart should be taken to pare off the burr.
The push-lever and record apindle should be cleaned from time to time.
It is recommended to play only flat sod quite clean records. The recorde dete rionate and wear out quickly if not kept sheltered from the dust. Transport of record changers Care should be taken, when forwarding, to place the apparatus in the exact position in the special packing with all the securing wedges in their correct position. The tarotable abaft and record spindle should be removed from their playing position und packed separately.
Adjustment If the record changer does not function correctly verify in the first place that the unit plate is in no manner distorted by the mounting device and that the weight in equally distributed between the four fixing screws. Pick-up landing position The pick-up urus has been finely adjusted so that the needle conc # on to the in " (25 cm.) record on a
9.9 16 " (315 min.) diameter circle, and on a 12 " (30 en.) record on 11-9 / 16 " (295 mm) diameter circle. There positions were arrived at after checking a very wille selection of records of various maker,
However, if an adjustment becomes necessary, regulate by means of the special screw near the bart of the pick-up arzn. The pick-up should never on any account be forced into position. Height of pick-up The pick-up in adjusted in such a way that a medium needle arrives at level with the turntable. If after attunement is necessary it must be executed by bending slightly in extremity of the steel wire forming the vertical abutment. The pick up should be rained for access to this abutment.

Auto-trip mechanism The record feeling mechaninert ja actiuped by the auto-trip meebeniam. If at the end of record, the auto-trip does not operate, that is the pick-up remains in the last

groove, examine first of all, if the record in question has a re- groove in its centre. Only records with run of progres can be played on a record changer. If this i, set the catre, proceed u follows:
Operate the " reject button.
Case No. l. The record changing mechanism parts: Take off the turntable et examine the trip lever leather. If this is worn, give it half turn to present a new surface to the striker. If badly wore renew entirely. If the leather is in good condition. then increase the tension of the friction spring by taming the friction adjusting, screw in a counter-clockwise direction, about half a turn is sufficient.
Case No. 2. The record changing mechanism remains immobile: This shows that the record changer is blocked owing to the hardening of the grease on the cams or the presence of an erratic particle. Clean the cams and gearings and lubricate again.

Record feeding mechanism
If a record does not drop from the record spindle or drops late, examine first of all if its thickness at the centre in standard (1.5 to 2,6 mm.) and if the centre hole in in order and without a burr. Verify also if the record spindle is clean.
If the defect is not caused by this, remove the records, start the record changer mechanism and then stop it just at the moment when the push-lever is at its maximum point. Then verify by means of a calibre that the course of the push-lever is in conformity to the dimension indicated on the sketch beneath.
If the contrary is the case, adjust this course by means of the bolt situated in front of the overarm. To do this, raise the overarm, loosen the lock-out and turn the bolt as far as necessary. Tighten up again by means of the lock-out and verify if the course is correct

Selecting mechanism for 10" and 12 " records
If an error occurs when the pick-up lands on the edge of the mixed record, verify in the first place the report feeding mechanism as shown on the sketch. If the adjustment of this latter is correct, control the freedom of the smallest feeler of the platform during the feeding operation.

Last record stop
If the record changer does not stop after playing the last record, verify if the larger feeler up the platform is quite free and emerges to its proper extent when there are no records or the platform. Verify also that the " Start Stop " button is quite free in all positions.

Turntable brake
The turntable brake is actioned by the auto-trip mechanism. If the brake does not work with sufficient efficiency on the turntable, the mechanism will overrun the regular stop position and the motor will not start at the beginning of new pile of recorder. This can be corrected by slightly turning the leather pad to present a new surface to the turntable.
Every unit is thoroughly tested and lubricated before leaving the factory.

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