Revox G 36 Service Manual Download Page 41

Page: 41 / 52

INDEX ORDER

N°

PART DESCRIPTION

SERIES

Ind

III

Push Button Assembly

1.736.550

Push Button Assembly Complete Colour 1035

x x

7140

1.736.550

Push Button Assembly Complete Colour 6760

7141

20.21.7203

Self Tapping Screw (Push Button Mounting)

x x x

7142

1.736.578-02

Push Button Grey Colour 1035

x x

7143

1.736.578-02

Push Button Grey Colour 6760

7144

25.16.1211

Push Button Retaining Pin

x x x

7145

54.04.0118

Diode, Noise Suppression 50V / 100mA
(Diode on Relay - socket Series III)

x x x 4 7146

50.04.0128

Switching Diode 50V / 500mA

1.736.587 Contact,

Stationary

7147

1.736.592

Contact,

Stationary

x x 26 7148

1.736.591

Paxolin Switch Lever

x x x

7149

1.736.588

Moving H Contact

x x x

7150

1.014.300

Solenoid, Push Button Release

x x x

7151

1.014.910-01

Slug, For all Solenoid

x x x

7152

1.736.551-05

Leaf Spring, Locking Bar

x x x

7153

1.736.551-11 Contact

Spring

x 8 7154

1.736.551-07

Push Button Spring

x x x

7155

1.736.150

Speed Selector Switch Complete

x x x

7156

1.736.151

Speed Selector Switch Complete 7.5/15 ips

Summary of Contents for G 36

Page 1: ......

Page 2: ... 3 Removal of capstan assembly 11 3 Electronic Description 13 3 1 Circuit checks and adjustments 13 3 1 1 Measuring instruments 13 3 1 2 De magnetising 14 3 1 3 Head alignment 14 3 1 4 Playback amplifier 16 3 1 5 Bias adjustment 17 3 1 6 Measurement of overall frequency response 18 3 1 7 VU Meter adjustment 19 3 1 8 Adjustment of head shielding 20 3 1 9 Channel to channel crosstalk 20 3 2 Tuning t...

Page 3: ...uipment a selection of adapter cables is available 2 Mechanical Description The machine employs three motors Two are identical and perform the wind and tension functions The third motor is large and drives the capstan It is of the pole switching variety and speed change is therefore effected electrically The wind motors are designed to provide pulse free torque Back tension is applied by electrica...

Page 4: ...rque Inset schematic B and diagram 7 736 001 002 6 refer The tape guide pins to the left and right hand side of the loading slot assist in achieving uniform tape tension due to the change in friction with varying wrap around from large to small spooling diameters A three digit tape counter is driven from the take up turntable by a rubber belt The translucent resetting knob of the counter is lit by...

Page 5: ...the spool flanges This is brought about by sliding shim washers of varying thickness onto the spooling motor shafts after removal of the bakelite brake drums To pull a brake drum off the shaft screws should be inserted into the three tapped holes 1 in fig 2 so as to serve as handles Care should be taken to prevent damage of the brake bands at this stage Where a brake drum has to be removed it is r...

Page 6: ......

Page 7: ...ing Depress the stop and play buttons simultaneously to energize the brake release solenoid If the movement is incorrect loosen the nuts 10 and re position the solenoid The front end brackets of the brake bands may be bent to achieve simultaneous release of both brakes The brakes should be kept clean and dry Do not use any oil or grease on the linings 2 1 3 Tape tension Back tension is applied by ...

Page 8: ...lenoid in the required direction 2 1 5 End of tape switch A Photoelectric end of tape switch Recorders with serial numbers from 58 000 onwards are equipped with a light sensitive auto shut off device It consists of a light source Osram 3644 the photoresistor ORP 62 and a printed circuit section containing two transistors see fig 1 The photoconductive cell is housed in the tape guide pin on the rig...

Page 9: ...he outer diameter of the tape guide On recorders with serial number 36 500 and up the sensing lever operates a gold plated wire contact This switch opens when tape tension is applied see BE in schematic Band 7 736 001 002 Adjustment should be carried out analogue to the above specifications for the snap action switch by bending the long wire loop In the resting position sufficient contact pressure...

Page 10: ...hen detecting any deviations from the figures quoted an accurate reading of the mains frequency should be taken first before investigating pinch roller pressure brakes etc On a 50 cycle power line a drop to 49 5 cycles will make the recorder run slow by 1 and this should be borne in mind when checking equipment with a specified accuracy of 0 3 percent 2 2 Routine maintenance 2 2 1 Cleaning From ti...

Page 11: ...mbly needs replacement unscrew the four fixing screws bend the pushbuttons to the right and ease the unit to a better working position For better access to the switch assembly the housing of the pinch roller solenoid should be removed by undoing the M 4 nuts pos 12 in fig 6 2 3 Removal of capstan assembly This may become necessary where the recorder is to be used on a mains frequency which differs...

Page 12: ......

Page 13: ...ollowing items are essential a 10 000 Ω V DC Multi range meter b VTVM with min sensitivity of 3 mV full scale c Low distortion audio generator d Appropriate calibration tape use REVOX Bezugsband or Bezugsband 19 DIN 45513 both of which have a frequency response corresponding to the G 36 equalization characteristic Where a test tape with response characteristics of the recorder under examination is...

Page 14: ...ge may be caused to a calibration tape by magnetised sound heads as they will tend to partially erase the high frequencies on the tape They may also have some adverse effects on the overall performance of the recorder 3 1 3 Head alignment Head adjustment should only be necessary when a head requires replacement or where the setting has been interfered with Five adjustment screws are provided I the...

Page 15: ...hase check method The azimuth position of the head gap on stereo tape recorders influences not only the signal level at high frequencies it also effects the phase relation between channels The criterion of minimum phase deviation provides a more accurate indication of correct gap angle than the adjustment for maximum output level To avoid a phase angle error of 90 the azimuth should first get alig...

Page 16: ...ape off the heads Connect a VTVM to the cathode follower output of each channel in turn A reference signal recorded at 32 millimaxwell per 1 mm of tape width should give an output of approximately 3 db below that specified in the technical data refer to 5 The frequency response section of the calibration tape is normally recorded 20 db below this level for measuring the performance characteristics...

Page 17: ...ias traps It must be observed however that the residual bias remains below the level specified under 3 1 1 Where a filter is not available the overall performance can not be tested while recording as bias leakage masks the audio signal It will be necessary to take all readings after first recording rewinding and then playing the tape again Any alteration of the bias current changes the remanent ta...

Page 18: ...he signal level is some 25 db below peak record level 3 dist otherwise the record pre emphasis may lead to tape saturation at high frequencies thus producing false test results Where the frequency response deviates from the specified tolerance of 2 3 db a slight re adjustment of the bias current may be necessary Any variation in bias has a pronounced effect on the frequency response If a fault is ...

Page 19: ...sensitivity of 7 db is required on the VU Meter to compensate for its ballistic characteristic The generator level should now be attenuated by 7 db and the trimpot on the meter amplifier adjusted for 0 VU indication on the meter Adjustment is made with the trimpots P 8 and P 9 fig 14 for channel I and II respectively Lacking a distortion analyser a reasonably accurate alignment is possible by the ...

Page 20: ...g infinite crosstalk rejection A crosstalk figure of 50 db can be reached in practice and is generally considered acceptable It may however still be irritating in such cases where extreme level differences exist in the recordings of adjacent tracks When checking crosstalk one should never listen to the dead channel with a wide open monitor gain Depending on the reserve gain available in the monito...

Page 21: ...on at 1 mV 100 kc s should be connected to pin 1 on the socket of V 5 Plate Channel I and the slug of L 1 Fig 14 is to be tuned for a minimum reading After connecting the VTVM or oscilloscope to pin 6 of the same socket Plate Channel II the slug of L 2 should get tuned analogue to the above Tuning of the bias filters on the cathode follower outputs V 9 and V 11 not obtained in the early version of...

Page 22: ...great Run at 3 3 4 for a few minutes Recorder will then pick up to 7 1 2 ips Pinch roller arm does not operate Dirty solenoid Dirty contacts in the push button assembly Dummy plug of remote control removed Clean and adjust solenoid 2 2 3 Clean and adjust solenoid 2 2 4 Connect pin 1 2 and 3 of the remote control socket Brakes do not release Dirty brake solenoid Dirty contacts in the push button as...

Page 23: ...be De magnetising the head 3 1 2 Bad treble response Dirty head Heads out of alignment Worn out heads Tape wrongly threaded Bias incorrect Clean the heads 2 2 1 Adjust the heads 3 1 3 Replace heads Thread tape as explained in the instruction manual Adjust bias 3 1 6 Absence of recording or insufficient recording Dirty recording head Defective recording head Dirty contact of recording push button I...

Page 24: ...track recorder 52 db 3 harmonic distortion Dynamic range 2 track recorder 55db at 7 ips 53db at 3 ips 4 track recorder 52db at 7 ips 50db at 3 ips Crosstalk Mono 60db Stereo 40db Oscillator bias frequency 70 kc s push pull oscillator Inputs per channel 1 Microphone 3mV Ri 0 5 MΩ max 600mV 2 Radio Tuner 50mV Ri 1 MΩ max 10V 3 Diode Aux 3 50mV Ri 47 kΩ adjustable Outputs 2 High Impedence outputs Eou...

Page 25: ...Case dimensions 19 x 13 x 12 Chassis dimensions with 10 reels 21 x 15 x 10 Colour grey All data are valid for the 2 track as well as for the 4 track recorder unless specified otherwise ...

Page 26: ...6 Circuit Diagram ...

Page 27: ......

Page 28: ......

Page 29: ......

Page 30: ...re 13 page 14 there is a considerable rise in the high frequency response of the record amplifier This response characteristic is necessitated by the standardised replay equalisation as well as by the type of tape emulsion utilised for recording The frequency response displays a peak around 30 kc on machines up to the above mentioned serial number In conjunction with the extremely wide response ch...

Page 31: ...REVOX G 36 recorders not containing these modifications can easily be adapted to the new response characteristic by replacing and or adding the above mentioned components ...

Page 32: ......

Page 33: ......

Page 34: ......

Page 35: ......

Page 36: ......

Page 37: ......

Page 38: ......

Page 39: ...ion errors the german version shall be the determinant When ordering plastic parts with the same order number but of slightly differing colour add colour code number SERIES The three columns indicate in which series a particular part is used Parts which are not directly interchangeable between Series are marked by the letter x in parentheses They have to be replaced by complete sub assemblies QUAN...

Page 40: ... Top Plate 1 736 851 Top Plate Complete x x 7021 Top Plate of Series I to be replaced with Top Plate 1 736 851 and Counter 1 736 502 15 x 7020 21 02 3375 Machine Screw M 3x12 Oval Head for Mounting of Top Plate x x x 6 7022 1 736 853 Plastic Cover for Pressure Roller x x 1 7024 1 736 500 15 Plastic Cover for Pressure Roller x 1 7025 1 736 500 13 Plastic Head Cover without Name Plate x x 1 7026 21 ...

Page 41: ...ode Noise Suppression 50V 100mA Diode on Relay socket Series III x x x 4 7146 50 04 0128 Switching Diode 50V 500mA x 1 03 1 736 587 Contact Stationary x 26 7147 03 1 736 592 Contact Stationary x x 26 7148 1 736 591 Paxolin Switch Lever x x x 5 7149 1 736 588 Moving H Contact x x x 8 7150 04 1 014 300 Solenoid Push Button Release x x x 1 7151 05 1 014 910 01 Slug For all Solenoid x x x 3 7152 06 1 ...

Page 42: ... 1 7157 1 736 150 10 Motor Wafer x 1 7158 1 736 150 06 Equalization Wafer x x x 1 7159 1 736 170 Recording Channel Selector Complete x x x 1 7160 1 736 170 03 Oscillator Wafer x x x 1 7161 1 736 170 02 Amplifier Wafer x x x 1 7162 ...

Page 43: ...for Motor with 2 Coupling Pins x x x 7085 05 1 736 135 Flywheel Complete for Motor with 4 Coupling Pins x 1 06 1 736 128 07 Washer x x x 1 07 37 01 0110 Spring Washer x x x 1 08 22 01 5060 Hexagon Nut x x x 1 09 1 736 138 02 Coupling Pin for Motor with 2 Coupling Pins x x x 2 7089 09 1 736 140 02 Coupling Pin for Motor with 4 Coupling Pins x 4 2 different types of capstan motors are used in the G3...

Page 44: ...50 Hz 7 5 15 ips 6 12 pol x 1 7084 02 1 736 128 08 Felt Ring Lubrication x x x 1 03 1 736 128 06 Grease Cup x x x 1 7086 04 1 736 130 Capstan Bearing Plate without shaft x x x 1 05 1 062 351 03 Thrust Washer Top x x x 1 06 1 736 128 04 Felt Washer x x 1 06 1 736 125 03 Low friction Washer Plastic Coated x 1 when replacing felt washer 1 736 128 04 with low friction washer 1 736 125 03 the steel shi...

Page 45: ...INDEX ORDER N PART DESCRIPTION SERIES Qu Ind III I II III D Head Support Block ...

Page 46: ... 027 114 Tape Guide Centre Piece Right Opt And Switch x 1 7135 15 1 736 222 08 Tape Guide Post Left Ser I II also right x x x 2 7037 16 1 736 250 Tape Guide Post Right Opt And Switch x 1 7038 57 99 0132 Photo resistor ORP 62 x 1 7039 17 1 736 222 03 Threaded bushing x x x 2 18 24 16 1040 Lock Washer M4 x x x 2 19 21 01 0456 Machine Screw M 4x10 x x x 2 20 22 01 8030 Hexagon Nut M 3 x x x 1 21 1 73...

Page 47: ... 736 200 03 Clip Pinch Roller Complete x x x 1 7112 59 1 736 501 06 Spacer x x x 1 7113 60 1 736 200 02 Pinch Roller Spindle x x x 1 7111 61 1 736 275 01 Lever x x x 1 62 21 59 6504 Allenscrew M 5x6 x x x 2 63 1 736 275 05 Compression Ring x x x 1 64 1 736 275 03 Adjusting Nut x x x 1 65 22 01 8040 Hexagon Nut M 4 x x x 1 66 1 736 275 02 Spindle x x x 1 67 1 736 275 04 Bracket x x x 1 68 1 014 910...

Page 48: ...04 1 736 358 Brake Drum Complete x x 2 7097 Brake Lining Available by the Metre 1 736 360 01 Mounting Spring Brake Drum x x x 7098 05 1 736 351 Brake Band Complete with Mounting Brackets x x x 2 7105 06 1 736 502 10 Brake Tension Spring x x x 2 7106 07 24 16 3032 Retaining Ring x x x 4 08 20 21 7153 Self tapping Screw 4x1 4 x x x 2 09 1 736 502 07 Angle Bracket x x x 2 10 1 736 502 14 Brake Releas...

Page 49: ...0154 Motor Condenser 2 0 5 µF Capstan Motor 50 Hz x 2 7118 59 15 4309 Motor Condenser 3 µF Spooling Motor 50 Hz x x 1 7119 59 15 4359 Motor Condenser 3 5 µF Spooling Motor 50 Hz x 2 7120 1 736 002 08 Turns Counter x 1 7121 1 736 502 15 Turns Counter Colour 1035 x 1 7122 1 736 502 15 Turns Counter Colour 6760 x 1 7123 1 736 851 07 Lens Counter x x 1 7124 31 99 0101 Belt for Counter x 1 7125 31 99 0...

Page 50: ......

Page 51: ...ier 2 Track 50 Hz x x x 1 7178 12 1 736 486 Equaliser Panel Complete 2 Track 60Hz NAB x x x 1 12 1 736 481 Equaliser Panel Complete 4 Track 50Hz x x x 1 12 1 736 487 Equaliser Panel Complete 4 Track 60Hz NAB x x x 1 12 1 736 491 Equaliser Panel Complete 2 Track 7 5 15 ips 50Hz x x x 1 13 58 20 0504 Trimm Pot Meter 500K VU Meter Amplifier x x x 2 7180 14 58 20 0104 Trimm Pot Meter 100K Cross talk C...

Page 52: ...198 01 54 02 0293 Double Phono Socket x x x 5 7199 02 53 01 0111 Remote Control Socket x x x 1 7200 03 58 11 6473 Potentiometer 47 K for Diode Input x x x 2 7201 04 53 03 0121 Mains Voltage Selector x x x 1 7202 05 53 03 0120 Voltage Selector Knob x x x 1 7203 51 01 0115 Fuse 0 63 A 220 V x x x 1 7204 51 01 0118 Fuse 1 25 A 110 V x x x 1 06 1 736 400 10 Remote Control Dummy Plug x x x 1 7211 07 54...

Search results

Summary of Contents for G 36

Reviews:

Related manuals for G 36

Brands by name

Popular brands

Revox G 36, Service Manual

Search results

Summary of Contents for G 36

Reviews:

Related manuals for G 36

Brands by name

Popular brands