Lubrication Chart - Dual C 839 RC Service Manual

11. Record/playback head
Remove the head cover 77 as described above. Solder off the
leads to the head. Remove the screws 72 and 73 and spring
71 and then remove the record/playback head. Insert the new
magnetic head. The screw at the right 72 must only be screwed
in approximately 4 revolutions. Using the left screw, adjust
the head so that the tape on a tape motion test cassette runs
smoothly. Final adjustment must be carried out as described
in the section entitled "electrical alignment".
12. Erase heads
Remove the head cover 77. Erase heads 68 must only be re-
placed in pairs.
13. Magnets
With the drive mechanism removed from the unit, remove the
4 machine screws 3. Remove the covering panel and with-
draw the magnet fixture 12 by loosening the grip screws 10.
Remove grip screw 17 and unscrew the mag nets.
When refitting the magnets ensure that magnet 4 at its stop
position positions the head slide 0.75 ± 0.25 mm in front of
its final position. Tighten magnet 5 so that the steel pin on
the lever 15 deflexes the wire strap 62 0.3 — 0.7 mm in its
operating position.
14. Bearing flange for flywheels, drive pulleys
Remove the flywheels as described above. Unscrew the 4
machine screws 40 and remove the covering panel 49.
Caution: do not twist the set of springs 35 on the record sa-
fety levers. Remove the relevant bearingflange or drive pulley
after unscrewing the countersunk head screws 47.
When refitting, take careful note of the description of the
various assemblies. Recheck axial play of the flywheels and,
if necessary, correct it to 0.2 — 0.5 mm.
15. Tape guide (up to unit no. 18000)
Remove the head cover 77 as described above. Remove the
clamping ring 67 and the spacing pu I ley 66. Raise the pressure
roller together with tape guide approximately 1 mm and
rotate it 1/4 revolution and then remove it from above (lift
the cover slightly).
Tape guide synchronisation should be between 30 and 60 mN
measured at the tape guide front edge. If necessary, bend the
tape guide limb with a pair of flat-nose pliers. By bending
both limbs by different amounts on each side, the height of
the tape guide and, therefore, tape motion may be adjusted
(figure 18).
16. Tape guide (from unit number 18001)
Unscrew the machine screw M 2 and remove the complete
tape guide fixture. Remove the adjustment bushing after re-
moving the grub screw.
Remove the tape guide and pressure roller.
Adjust tape guide synchronisation to between 30 and 60 mN
as described above.
Adjust the height of the tape guide for tape motion at the
adjustment screw (the screw should afterwards by secured
with locking lacquer).
The erase head tape guides use for aligning the guides flush
serve as fixed reference points. The tape must not bend at
any tape guide to such an extend that damage results.
Set the axial play of tape guide and pressure roller at the
adjustment bushing (0.02 — 0.05 mm).
17. Take-up friction and tape speed
(Refer to alignment instructions for motor electronic system,
page 7).
18. Cleaningnubrication
Always clean the unit when servicing or repairing it. In order
for the record/playback head 70 to function Properly, the
erase heads 68, the pressure rollers 65 and the capstan should
always be kept in a perfectly clean condition.
We recommend the use of a cloth or cotton wool bud dipped
in methylated spirit in order to clean these sections. Never
use metal objects. The surface of the head must never be
touched with bare hands.
Fig
7
73 72
71 68
t rt
ws
_L. rt ws rt ws 1 ws
•.__„,___} \—_,__J
__,,,__./ ,,—,,—/
blau
braun grau schwarz
blue
brown
grey black
bleu
brun
gris
noir
Fig. 18
ws = weiß
withe
blanc
rt = rot
rad
rouge
Band lauf höher Band lauf tiefer
,Stellschraube
6
All bearings and sliding points on the unit
e .a a. ca-
ted at the factory. Re-lubrication is
several years since the most important bee- -g.
ded with oh I retainers. The rnotor a -e e...9 -c
life oil retainers and, therefore. reo _ - -
10 mN = 1 p
Lubrication chart (C 839 —
E
Lubrication points
_Cr
—
Rywheels ex i-',772
(Capstans
Pressure rollers
' 2 e:3"
Head slide
3 0Jice 'oh
Losem
Beering
in
six- ap
Fin.
contact
with
wirearc
ead sride
-ae 2-'ace of locking
magnet 5
-
Isoflex PDP 40
adhesive oh , Renotac
Molykote peste
ad hesive oil, Renotac
adhesive
=e•-• z
24