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SERVICE
MANUAL
1B40-1B50-1BBDD-1B70
TAPE RECORDERS
~·
_;. ,,~·· IMJ
$2.50
IDENTIFICATION CHART
MODELS 1640, 1650, 16600, 1670.
!KEYED TO ILLUSTRATION AT RIGHT!
1. Suppl y Reel Ho l der
2. Supply Reel
3. l eft Channel Spco~cr
(Not in 1660D. Outboard In 1670)
4. Tope G ui d e Roller
5. Automa tic Shut- Off l ever
6. Drive Cop1tan Storage Post
7. I ndex Counter
8. Editing Guide
9. Take - up Reel Ho lder
I 0. Toke- up Reel
I I. Righ t ((ronnel Speaker
(Not in 1660D. Ou tboard in 1670)
1 2. Drive Capstan
13. Pi nch Wheel
14. Pau>e lever
15. Rewi~d / Fasl Forward Control
16 . Stop / Stor l Con1rol
17. l eft Channel Miaophonc Inpu t,
18. Right Channel Microphone I nput
19. l eft Channel Volume Control
20. lef t Channe l VU Meter
(Oual Purpose Meter on Madel 1640)
21. Modl!l 1640 : l e ft / Righi VU Me ier Switch
Model. 1650 and 1670 : M onilor-Norma i ·Mule
Speqkcr Switch
Model 1660D: R/ l - NOI'I!IOI · l / R Channel Transfer LlV)---"'~---,
Switch {ll) - -- --
l -=-==='-'
22. Right Channel VU Meter
(Not i n Mod el 1640 )
23. Righ t Channel Vol ume Control
24 . Left Channel Play / Record Switch
25. Righ t Channel Ploy/ Record Switch
26. Tone Control
27. Power Switch
28. Record Indicator l igh t
29. Power Cord Connection
30. Stereo Headphone Jock ( 1650 & 1670 J
3 1. Rig h t Hum Ad j ustment
32. l eft Hum Adjustmen t
33. Right Cho M cl Preorn p O utput ( 16 4 0, 1650, 1670 I
34. l C!ft Cho nnel Pr,omp Outpu t ( 1640, 1650, 1670)
35. Right Channel Phono/ Rodi o Input
36. l ei I Channel Phon of Radio Input
37. Ri ghi Channel Speaker Output (I 6 40 . 1650, 1670)
38. Left Channel Sp eaker Output ( 1640, 1650, 1670)
39. Right Cha nnel Twee te r Oulpul ( 1650, 1670)
40. Loll Channel TwDetcr Ou tput (1650, 1670)
4 1. Rig hi Cho nnol High Levol Output II660D only)
4 2. l ei I Cllonnol High Level Output ( 1660D o nly)
43. Ri ghi Channel Low Level Output ( 16600 o nly)
44 . l ell Chonnal l ow l evel Outpu t ( 1660D onl y )
FUNCTIONS OF CONTROLS
Power Switch: stop mode, the lifter pushes the tape away from the heads
to prevent excessive wear during the fast rewind and fru;t
Moving Lhe power switch to the ·'ON" posilion applies forward opera tions. This also mules the ~ound during these
power to the motor and amplifier. In the "OFF" position, modes.
power is cut off to the entire unit.
Volume: Stop-Start:
A separate volume control is provided for each channel. Starts tape movement i11 "Play'' or "Record" position.
The volume control varies the playback volume, and the Stops tape movement when moved lo the "Stop'' position.
record level when making a recording.
Rewind-Fast Forward:
Tone: Fast Forward position advances U1e tape onto the take-
The tone control setting determines the [reguency re- up reel at a fast rate of speed. Rewind position winds the
sponse of both amplifiers. Tone controls do nut. wor k during tape onto the feed reel at a fast rate of speed.
record.
VU Meters: Pause Lever:
In t.he "Up' posilion, pinch roller is moved away from
The VU Meters are used to monitor the record level
capstan, and take-up torque is removed from take-up spin-
when recording, and to balance stereo play. Meter indication
dle. Tape stops instantly. This permits an adjustment of
should be between - 3 and -7 for best recording results.
the record level without tape m ovement. \Vhen lever is re-
tmned to "Down" position, the tape movement begins.
Record Switches:
To operate, depress either or both record switches, then Index Counter:
turn the stop/ start conh·ol to "start. .. This holds the record
switch in record mode. Provides a means of locating desired selections on a
When the stop/ start control is re turned to "stop," the reel of tape without skipping and h unting.
record switch automatically snaps back to play mode_
Hum Adjustment Controls:
Channel Transfer Switch: (1660-D) On Lhe l'ear paneL next to lhe A .C. Receptacle are two
This switd1 internally transfers the output of one chan- openings, these are the Right and Left Channel hum ad-
nel over to the input of the other channel. A microphone justing Potentiometers. They are screw driver adjustment.>.
or radio/ phono addition is added to the transfer receiv- Without tape on the unit, turn the volume up full and ad-
ing channel during recording. just the controls for minimum hum on each channel.
The process may be repeated back and forth between
channels to make a multiple recording. Auto-Stop Switch:
When tape holds the auto-stop switch ''U p," the motor
Tape Lifter: circuit is completed and the motor runs. If the tape breaks,
The tape lifter is under the head cover and is operated runs out, is of insufficient tension, the switch lever fa ils,
by the stop/ start control. When the stop/ start control is in breaking the circuit, shutting off the motor.
INPUT AND OUTPUT JACKS
Microphones: Outputs:
1660D . .. There are two high and two low level preamp
A micropho11e input is provided for each channel. outputs. each adjustable by the volume controls. These out-
These input jacks a re located on the front panel to the left puts are used to collllect the 1·ecorcler playback system to
of the left channel volume control. an external power amplifier. The output jacks are located
on the rear panel.
The high level outputs are used with standard tube
Note: When using the P hone-Radio inputs, the mi- type amplifiers that have tu_ner, auxiliary or other high
level inputs.
crophone plugs must be removed from the mi-
The low level outputs are for solid state amplifiers.
crophone jacks. Te5ts will show which is best for each individual case.
The high and low level outputs are low impedance cath-
ode follower outputs allowing for lvnger interconnecting
c.:ables without line losses.
Phono-Radio Input: 1640 .. . On the rear (Janel are two external speaker jacks
and two high impedance p reamp outputs.
Each channel is provided with a Phono-Raclio input
1650 & 1670 . . . Has the same outputs as the 1640, plus
for making direct recordings from a radio. phonograph, or two phono type jacks for extension speakers to work with
tu ner. These inputs are located on the rear panel. the internal speakers. There is also a stereophone jack.
3
PARTS IDENTIFICATION
Fig. 2. Top View of Tape Transport.
OPERATING INSTRUCTIONS
Hook-Up Procedures: (1660-D) Threading the Tape:
1. T he outputs, high and low level are cathode follower. 1. Place a full reel of tape on feed spindle. Place an empty
low impedance preamp outputs. reel on t.akeup spindle. Secure reels in place with rubber
The instructions of the external power amplifier and or reel holders provided.
t uner should be followed. However as a rough guide the
following may be helpful. 2. Unwind aboul 14 inches of tape from feed red. H"old a
I nterconnecl .. . . sect ion of tap!' taut and thread p er photo. Make sure
!.ape pulls automatic tape shutoff switch arm u p to "On"
High l-evel Output .. . to .. Tube amplifier. po.>ition.
· a. High level input
b. Auxillary input 3. TnsPrt fre~t end of tape into one of the radial slots in hub
c. Preamp input of takeup reel. H old tape end in place and turn reel
d. Tuner input several turns counterclockwise to secure tape to the reel.
Low Level Output ... to .. Transistor amplifier.
a. Input
To Make a Stereo Recording:
b. Preamp input
c. Tuner input
1. Connect recorder to 110-125 volt 60 cycle power source
d . Auxiliary input
with power cord provided. Turn power switch to "Power
Rad/ Phono I nput ... to .. Tuner Output On.''
to .. Amplifier T ape Out
to .. Amplifier Preamp Out 2. Thread the t.ape. Set Index Counter to zero.
to . . P hono. Ceramic Cartridge
to .. Phono. Preamp Out 3. Connect signal source to proper input.
to .. parallel with TV speakers a. If microphones are used connect them to microphone
to .. parallel with Radio speakers jacks. L evel will be controlled by the volume controls.
4
Fig. 3. Bottom View of Tape Transport.
b. If a phono or radio source is used connect their out- 4. Turn Start-Stop knob to "Start" position. Adjust volume
puts to the respective channel Phono-Radio input for each channel. Both tracks of a 2-track stereo tape or
jacks. Level will be controlled by the volume controls. tracks 1 and 3 of a 4-track stereo tape will now be played.
4. Push Pause Lever to "Up" position. 5. Tape may be advanced rapidly or rewound , after Start-
!i. Hold record switches depressed. Stop knob is placed in ··stop" position, by using Fast
Forward-Rewind knob.
6. Tum start/ stop control to " Start" posit1on. This hold;;
the record switches down in record mode. 6. To play tracks 2 and 4 of a 4-track stereo recording after
tracks 1 and 3 have been completed, do not rewind tape.
7. Start signal source to set recording level. VU Meters Remove full ree\ from takeup spindle, turn it over. and
should read -3 to - 7 on the average. place on feed spindle. Proceed as in Steps 2-5 above.
8. Release the Pause Lever (down) to start tape. Tracks
1 and 3 are now being recorded.
9. When recording is completed, or when the end of the Monaural Recording and Playback:
reel of tape is reached, return start/ stop control to
·'Stop'' position. Record switches are automaticaUy re- Proceed as indicated for stereo operation but use only
leased to return to play position. jacks. controls and switches for one channel. Volume con-
trols for the unused channel should be set at zero.
10. T o record tracks 2 and 4, remove full reel from take-up
spindle. turn over and place on supply spindle. Proceed To record four monaural tracks. use left channel first.
as in steps 2 - 9. recording track 1. Reverse tape by removing full reel from
Lakeup spindle, turning it over. and placing it on the feed
To Play a Stereo Recording: spindle. Continue to use left channel while recording track
1. Connect recorder to proper power source with power 4. Reverse tape and use right channel to record track 3.
cord provided. Turn power switch to "Power On." Rever.se tape again and continue to use right channel in
order to record track 2.
2. Thread the tape. Set Index Counter to zero.
3. Locate desired starting point by using Fast Forward- To play back four monaural tracks. use the same sequence
Rewind knob while observing Index Counter. of tape sides and recorder channels as when recording.
5
SOUND-WITH-SOUND RECORDING
This is a procedure by which you may record yam favorite orchest ra on one channel, and then play or sing with the re-
cording in such a manner as to make the playback sound as though you were " right there .. with the orchestra. Or it may
be used for language study. with the teacher's voice on one channel and your responses which may be erased and re-re
corded as often as desired) on the other channel. ROBERTS Language Laboratory Tapes. available from your R oberts
dealer, have tne instrucor's voice pre-recorded in this manner in fo ur differe.nt languages.
PROCEDURE:
1. Make a master recording on Track 1. using Left chrumel only. Turn Right channel volun1e controls to zero and fol·
low procedure m1der "To Make a Stereo Recording," using Left channel only.
2. R ewind tape.
3. Record on Track 3 , using Right channel only while listening to Track 1.
4. Rewind t.ape.
5. Play back recording, as in stereo play. Master recording will be heard on Left channel and added recording will be
heard on the Right channel.
6. Track 3 may be erased and rerecorded without disturbing master track by repeating Steps 2 through 4.
SOUND-ON-SOUND RECORDING (1660D ONLY)
1. Make original recording on Track 1 using Left channel only. Turn Right channel volume control to zero and follow
procedure under , ''T o Make a Stereo Recording."
2. Rewind tape to beginning of original recording.
3. Set Channel Transfer Switch io "L to R " position.
4. Push Pause Lever up to "Stop' ' position.
5. H old Righi R ecord Switch depressed and turn Start-Sto p knob to "S tart'' position.
6. Connect Right challllel microphone. Apply sig11al to microphone and adjust the Right channel volume control for ap-
proximately half the normal recording level reading on the Right channel VU Meter.
7. DO N0'1' READJUST THE RIGHT CHANNEL VOL UME CONTROL AFTER PRESETTING FOR THE MIC-
ROPHONE RECORDING LEVEL. (V:! ·Jormal)
8. Relea~e Pau:e L ever and ma ke a tdal recording of the Left cba~el trSllSfer and the R ight channel microphone added.
9. Adjust the Left channel volume control only, while watching the Right channel VU Meter reading. The Right chan-
nel VU Meter should be reading full normal. Half of the reading will be the Left cbrumel transfer ru1d the other half.
the Right channel microphone.
10. R ewind the tape. play the trial recording. If the test run was satisfactory. proceed with the final recording by re-
peating Steps 2 !hrcugh 9.
11. Playback recording. Sound-On-Sound recording is on Tra ck 3 (Right channel ) so volume controls for Left channel
should be set to zero. (NOTE: The original Track l recording of the Left amplifier is still intact a t this point, so
Steps 2 through 9 may be repeated if the final recording w as not satisfactory.)
12. The abo\·e process may be repeated, using Track 3 as the original recording and add more material to it for a rnul-
tirle recording. In this case the Channel Transfer Switch should be set at "R to L " position, and the L eft channel
microphone input will be used.
ASSEMBLY - DISASSEMBLY
Assembly (mounting): (1660-D) For Access to Top of Tape Deck:
1. Check for dearance, (deck & prean1ps, reels, ease of op- l. Remove Start-Stop Jmob and Fast F orward-R ewind knob.
eration. etc.). Transfer cutout pattern from template to
panel. Cut out panel open ing.
2. Remove 3 transport deck mounting screws, capsta n bush-
2. Remove side angle bra::kets {rom metal cage. ing storage r ost.
3. Install un it into panel cutout. 3. Pry out pinc:hwheel cap. take out pinchwheel mounting
screw. and lift oU pinchwheel.
4. Reinstall side angle brackets onto rne.tal cage, and press
up against underside of panel.
4. R emove bc>th reel tables after taking CJut reel table
5. If panel is .1f2" or mar~
thick, fasten angle brackets from screws. Note humber of fibre spacers under reel t ables
underside with wood screws, into panel. as they are removed.
/2" thick use fancy headed bolts and
6. If panel is less than 1
nuts clear through panel. 5. Lift off transport deck panel.
6
MAINTENANCE INSTRUCTIONS
LUBRICATION
Lubricate the following parts every ththe under moderate usage, and once a year unde< conditions
of occasiona1 use. 4. SatuTate the felt washer in the retaining cup of the
drive capstan with light machine oil.
l. Feed and take-up spindle shafts with two drops of light
machine oil on each shaft.
Caution: Do not allow grease or oil to remain on any of
2. Rewind idler bearing and wind idler bearing. with two the drive surfaces, or on plastic surfaces or any part touch-
drops of Light machine oil on each bearing. ing the tape.
CLEANING
The capstan, pinchwbeel, tape guides, and .reco.rd/ play the tape passes these parts. Clean these parts periodically
head and erase head accumulate a tape oxide coating as with a soft cotton swab dipped in alcohol.
MECHANICAL ADJUSTMENTS
1. Record-Play Head sure should be between 1,000 and 1,150 grams when the
unit is operating at 7% ips.
Height-Loosen the two mounting nuts at the side of
the .head mounting bracket. M ove the head so that the top
pole piece is even with the top edge of the tape. Gently
tighten the nuts. 6. Rewind Intermediary Idler
Azimuth-Place a prerecorded azimuth alignment tape
on the recorde.r. While playing tape alternately tighten Adjust the intermediate wheel spring to obtain about
upper and loosen lower head mounting nuts or vice versa 50 grams of pressure equally exerted to both the rewind
until position of maximum output is found. idler wheel and the rubber ring on the supply reel shaft
assembly. Make adjustment in the rewind mode.
2. Erase Head
The erase b ead height is adjusted in the same manner 7. Supply Spindle Tension
as the Record -Play head.
A change in torque is accomplished by either adding
another metal washer next to the one in the clutch assembly
3. Brake Shoes which increases tension, or by removing the existing one
which has the r everse effect.. See exploded view for location.
When brake shoes become worn, loosen the mounting
screws a nd rotate the shoes a few degrees until a new brake The required tension is determined by placing a stand-
surface is exposed to the supply and take-up reel discs. ard seven inch reel with a two and one fourth (21,.4) inch
hub diameter on the supply spindle. The reel should have
twenty six feet of leade.r tape wound on it. Attach the end
4. Rewind Idler Wheel of the leader t.ape to a scale with a range of 0 to 250 grams.
P osition the scale vertically with respect to the reel hori-
T o bring the wheel in alignment with the rewind reel zontal axis. Exert a steady pulL The required torq ue should
shaft adjust both the idler load spring and the rewind roller. be between 145 grams and 160 grams.
The pressure on the knurled motor bushing should be about
50 grams during the rewind operation.
8. Take Up Spindle Tension
5. Pinch Wheel
The procedure is identical as the supply spindle, ex-
To bring the wheel in alignment with the capstan shaft cept the required t orque is between 180 grams and 220
adjust the pinch w.heel load spring. The pinch wheel pres- grams.
7
G NERAL TEST PROCE
E DURES
NOTE: Whenever an external test instrument is used fr om an amplifier output, an 8 ohm resistor should be placed
across the amplifier output or the test instrument input, if the use of the test instrument disengages the
amplifier speakers.
II Preamp outputs are used for measurements, use a 270K 1W load resistor.
During Record modE'. an internal 8 or 10 ohm dummy load resistor is automaticaTiy inserted to replace
the speakers.
Anytime a high level signal is used, the wavPform mould be checked for djstortion on an oscilloscope.
Output:
Play back at full ,-olume and tone. a 700 cps tone. recordE'd at 0 ob. as measured on an external laboratory
type VU Meter.
Measure the output on the same type external VU Meter with the recordet· termnated into 8 ohms.
Square the resultant voltage n·arung from the VU M eter and divide by 8 ohms to get the RMS power output
in watts. ( P =E 2/ R ) .
Signal-To-Noise:
P lay back a 700 cps tone pre-recorded at 0 db, as measur0d on an external laboratory type VU Meter.
Adjust the recorder volume control until an external VU Meter from the output reads 0 db.
Without changing the recorder volume control setting, stop the tape motion wHh the Pause Lever and 1
·ead the
external VU Meter. The VU Meter is now reading residual noise only, no signaL
The reading in db of the residual noise level at that volume setting is the signal / noise ratio at 0 db level.
Frequency Response:
NOTE: First clean and demagnetize and adjust azimuth of the heads.
Set the counter io '000' and record a - 12 db line input 700 cps tone at -10 db as measured on an exter-
nal VU Meter. (If input meter not availa ble, set recorder volume control 1/.t turn open and adjust the os-
cillator output, for - 10 db amplifier output. )
R ecord the 700 cps tone at - 10db for 1 0 digits on the counter, then change tones on the oscillator for 10
digi ts per tone. without changing the oscillator output level or the recorder volume control setting.
The tones to be recorded after the 700 cps reference tone are 50, 100, 250, 500, 1000, 2.5K, 5K, 7.5K, lOX,
12.5K, 15K, 16K, and 17K cps for 10 digits each.
After recording above, rewind the tape to the beginning '000', and set the tone control for the 'fla t' setting for
the speed that is being used.
Play the 700 cps lone reference frequency at the beginning of the tones and adjust the recorder volume for an
output of - lOdb on an external VU Meter. Do not change the volume or tone control settings after the 700 cps
- lOdb is sd.
R ead the external VU Meter evpry 10 digits as the tone changes from the 50 cps to 17K cps.
T he variation ::. from the - IOdb, 700 cps reference frequency original setting, is the frequency response,
which may be plotted on log paper for a curv(' o1· simply by the numbers.
Wow And Flutter:
Play back a 3000 cps standard prerecorded wow and flutter tE'st tape, that guarantees a wow a nd flutter within
.07% . a nd read the E'ffeclive value on a wow and flutter meter.
8
SPEC~ &PROCEDURES
Hum
At max. volwne -30 db ( - 40 db at preamp)
At min. volume -60 db
Signal-to-Noise Record to Play -43 db min.
Pre-recorded - 44 db min.
Wow & Flutter .2% max at 7%
.3% max at 3%
Tone Conlrol - 12 db at 10KC
+ 13 db at lOKC
Head Current (OSC, Freq. lOCke)
Erase 12 MA to 15 MA
Bias .54 MA to .56 MA
R ecord .029 MA to .031 MA@ lKC
Power consumption at 117 V.A.C. 60 cps 55W (1660D) BOW (1640-1650-1670)
Erasure R ecord/Play at 0 db, 1000 cps
- 42 db using 1KC filter
Fuse: 1 % A. 250V.
Gain from standard operating level pre-recorded tape
7¥2 ips volume full .4 volts at preamp minimum
2 M V at mike for 0 level record
125MV at pbono for 0 level record
Crosstalk
R ecord Ch # 1 at 0 db, 700 cps
Play Ch #2 at same setting that Cb # 1 is set at for .25 V output on Ext. meter at preamp output -55 db min.
Cross Channel R ejection
R ecord both channels at 0 db, 700 cps
Play tape and set both channels to .25 V at preamp output
Reverse tape and play -55 db minimum
9
TAPE DECK PROBLEMS
j Capstan does not rotate. Troubles with motor -"' 1~,oken field coil. Check field coil with tester, and replace motor if coil IS broken. I
H Defective motor starting capacitor Replace I
H Rotor shaft dragging due to lack of oiL Overhaul motor. Clean and re·lubncate oilite metal. \
Troubles with power transmission
mech.anism.
r- y Some foreign matter exists between rotor and stator.
---1 Broken capstan
.
dnve belt.
Check and eliminate foreign matter for free rotation of rotor.
Replace belt. I
1
---i Capstan drive belt off of driving position. Place belt in position. I
-1 Motor bushing slippmg on motor shaft. Tighten mounting screw. \
-i Oil attached to motor bushing and/or flywheel Wipe off oil with cotton swab soaked in alcohol. j
r1Decreased motor torque. Check motor torque and replace motor. j
I Capstan rotates in Stop position, but
tape does not advance when switched Troubles With motor. WDefective Replace I
to Play pos1t10n.
Troubles with power transmission
mechanism.
f-rl_ Motor bushing slipping on motor shaft.
Capstan drive belt stretched
Tighten mounting screw. 1
Replace belt. I
H Oil attached to motor bushing and/or flywheel. Wipe off oil. I
H Capstan bushing sllping on flywheel shaft. Tighten capstan mountmg screw. I
H Excessive tension in Takeup/Supply reel table assembly. Readjust tension. !.
rl_Oil attached to capstan and/or pmch wheeL Wipe of oil. I
Y Insufficient pmch wheel pressure. Check and re-adjust pinch wheel pressu,re. I
!.Capstan advances tape. but take-up reei-rl Reel shaft dragging due to lack of oil. Check take-up reel shaft assembly. Overhaul reel shaft assembly: relubricate. Replace
does not take up tape.
H Take-up idler wheel does not rotate properly. Check idler wheel. Replace if necessary. I 1
reel shaft assembly If not repairable.
I
H Oil attached to idler wheel and or ro-
ller on take-up reel shaft assembly.
Wipe off oil. I
Y Take-up idler whee! does not keep good contact. Check idler tension spnng. Replace spring if necessary. J
J
w
Check lever
ITake-up flinctwns normally. but tape
speed lower than regular speed.
jrl Troubles with motor. Rotor shaft dragging due to lack of oil. Overhaul motor. Clean and re-lubricate oilite metal. J
Defective motor starting capacitor Replace I
~Fluctuation in power supply. Check line voltage and cycle. Use voltage regulator 1f line voltage is lower than standard. I
Troubles with power transmission
mechanism.
Qlpstm drive belt stretched and slipping on motor bushing Replace belt. I
Capstan drive belt not in correct driving position. Place belt in position. J
Oil attached to motor bushing and/or flywheel. Wipe off oil. I
!wow· flutter. Irregular tape movement. r- ---1 Troubles with motor. Rotor shaft dragging due to lack of oil. Overhdul motor. Clean and re-lubricate oilite metal. J
~Troubles with power transmission
mechamsm.
r-- W Defective motar starting capacitor
H Take-up, supply reel shaft dragging or excessive tension.
Replace I
Check reel shaft assemblies. Replace reel shaft
assembly if tension not adjustable.
I
H Capstan drtve belt stretched and slipping. Replace belt. ]
H Unbalanced flywheel rotation. Check balance. Replace flywheel. I
H Rubber on pinch wheel deteriorated. Replace pinch wheeL I
H Pinch wheel or tape guide does not rotate smoothly. Check and replace defective part. Clean and re-oil
if it again provides smooth rotation.
I
H Dust on heads. Clean heads. I
H Insufficient pinch wheel pressure. Re-adjust pinch wheel pressure. l
H_Gapstan bushing slipping on flywheel shaft. Tighten capstan mounting screw. I
Y Worn-out idler wheel or no oil. Replace worn-out Idler. Lubricate oilite metal in center of idler. I
IUnit does not operate in Fast. ForwardJ-n Take-up reel shaft does not rotate even Troubles with power Oil attached to take-up idler wheel or motor Wipe off oil. J
without placing recording tape on unit. transmission mechanism. bushing.
Loose motor bushing. Tighten motor bushing moWlting screw. l
Take-up idler wheel does not fllilction properly. Check and readjust idler wheeL I
Take- up reel shaft assembly does not function
properly.
Check. clean and re-oil reel shaft
assembly.
J
y_ Take-up reel shaft does not rotate when
recording tape IS placed on unit. Troubles with motor.
Check lever
Decreased motor torque.
I /Check motor torque. Replace mo -~
tor if required.
Defective motor starting capacitor Check and replace I
ITroubles with power . ~
Excessive slippage of clutch mate-
rial (felt} in take-up reel shaft Check take-up reel shaft assemblyj
Jtransmission mechanism. assembly.
I Tape guide roller does not rotate smoothly. Check guide roller. Re-Oil or replace.!
Take-reel warped and sticking to
Defective reel. Check and replace reel.J
deck top panel.
IUnit does not rewmd tape. f-~ Supply (rewind) reel shaft does not rotate Troubles with power trans- Oil attached to rewind idler or mo-
Wipe off oil. l
even without placing recording tape on unit. mission mechanism. tor bushing.
]Intermediate idler(black bakelite
Iwheel} not working correctly.
Check internal idler. I
Loose motor bushing . Tighten motor bushing mounting screw. l
. jRewind idler does not rotate or not
Check rewind idler. Clean and re·Oil-l
Jin position.
~upply reel shaft assembly does no
~tate smoothly.
Check supply reel shaft assembly.
Clean and re-oil
I
y Supply (rewind} reel shaft does not rotate
when tape is placed on unit.
rrlTroubles with motor. Decreased motor torque
]Check motor torque. Replace motor
lif not repairable.
I
Defective motor starting capacitor Replece I
~Trouble with power trans- Excessive slippage of clutch mate-
mission mechanism. rial (felt) in supply reel shaft assembly.
Check supply reel shaft assembly.
I
Tape gmde roller does not rotate. Check guide roller. Re-oil or replace. _j
!supply (rewind) reel warped and stick-
Y Defective reel.
ling to deck top panel.
Check and replace reel. l
Loose tape winding after being Decreased back tenswn of take-up and supply reel shaft
placed in Rewind or Fastforward Disassemble reel shaft assemblies and strengthen back tension.
mode. assemblles.
Tape spills when stopped from Excessive sllppage of felt clutch matenal m take-up and Readjust slippage of felt clutch matenal.
Replace defective reel shaft assembly if this
Rewind or Fast forward mode. rewmd reel shaft assemblles.
readjustment IS difficult.
Reels of different s1ze are used. For example. 5· reel on
Always use reels of same size on both Sides.
take-up s1de and 7~ reel on supply Side.
Break does not functwn properly. Worn-out brake shoes. Check and replace brake shoes.
Oil attached to surface of brake shoes.
Loose brake shoes.
Brake lever does not function properly. Check and re-adjust brake lever.
PenodJcal clack noise when
Worn-out and ragged Idler wheeL Replace idler wheel.
rewmdmg or fast forwardmg tape.
-
00
Loud motor VIbration. Loose motor mountmg screw.
Defective motor starting capacitor
FAST-FORWARD MECHANISM
Turn the FAST FWD-REWTND knob (A l to ~FAST FWD·
position, and the cam (B) under the knob pushes up
the Lever (C). The Tdler tDJ moves in to the space
between the Plastic Roller IFl above the Take-Up Reel
Spmdle and the upper part of the rotating motor driv
bushing to transmit the motor rotation to the take-up
reel spindle. At the same time, the brakes (H ) and {I)
come off the reel spindle to free the Supply Reel Spindle
(G l, thereby allowing fast winding of the tape onto the
take-up reel.
Free Rotation High-Speed Rotation
J
REWIND MECHANISM
Turn the FAST FWD-REWIND knob fA) to "REWIND~
position, and the cam (B) under the knob pushes the
Lever (C) up. The Idler (D) moves into the space bet-
ween the upper part of the rotating Motor drive bushing
(E) and the Intermediate Pulley (F) to transmit the high-
speed rotation of the motor through the Intermediate
pulley to the Supply Reel Spindle (G ). At the same
(l01v~
IC
time, Brakes (H) a nd (I) come off the reel spindle to
n.
free the take-up reel spindle r thereby rewinding the
tape into the supply reel at a fast speed.
\.....
~-==- High-speed Rotation
·
~ (~tP (\~II '
;..~
0
Free Rotation
0 "--.__/ ·J r'
'-......-/
\.-; , i I I~
Q____D--o
0I
Take- Supply-
STOP CONTROL
Pinch ITo!r.e-up [!iewtnd up-s1de side
Modes of Operation Roller Idler Idler Push the Stop lever to qSTOPh position, brake rubber
Wheel Wheel Brake ! Brake (A), and (B) depress reel spindles to stop rotation of the
1 l STOP
a X X X 0 0 reel spindles.
As brake rubber depresses the plastic rollers under
I the reel spindles, no friction works on the tape itself.
(b ) FAST-FORWARD X 0 X X X
c) REWIND X X 0 X 0
II
d ) RECORDING
PLAYBACK 0 0 X X X
I
NOTES: X-marks indicates ~open" and
0-marks "engagedh
10
~SCREW(2) ~S CREW
~ REEL TABLE (3) ' REEL TABLE
c:::=====t=:s::P===:f
SPINDLE TABLE (z Y)
SPINDLE TABLE
FELT WASHER
FELT WASHER
.....----- DRIVE RING {).5)
CLUTCH PLATE
(2~)WASHER SPRING (:z 7}
WASHER - -------.
FELT WASHER _ _ __ @RETAINING RING {29) _ _ - - - ®RETAINING RING
C::::==l===:r CLUTCH Dl SC ( 3o) ===t==== CLU TCH DISC
WASHERS--~~~~~~ STAR SPRING WASHER (3J) ------
~~~a===::::~- WA SHERS
(:2-g)
__ _ !3)_ 6RETAINING RING (zq) __ - ®RETAINING RING
(33 ~-. .,
.
~~~~--~~----- SCREWS----------~~--~~~
11
H~~~~:JIWE~fS~S~P~I~N=DL:E~('i?~~N Tt N G p LA T~E:=:~;;~~ftf~~s:~/ . , B ASE PLATE
~ NUT ------------~--~~r-~
SUPPLY REEL SPINDLE ASSEMBLY TAKE-UP REEL SPINDLE ASSEMBLY
# 62-49 #62-50 5-20-64 A
DATE REV. APP.
N
0
"RAD./PHONO
'-
'-
MI c 'ROPHONE
.------11~~ 12AX 7 r-- ~ 12AX? 1-+--e----:~:»...,.t---1 ~1'2AU? t------t~ 12AU7
r--tcATHODE VOLUME C.A.THOl>E CATHOt>IE
? CONTROL
{ '----e------+--to'" H I~H L-EVEL.
~
OUTPUT