Altitude-knob adjustment
RESTRICTED
1. Adjust-
ment of
the
A I -
titude
Knob
Fig. 32
inner altitude spring case fits over a friction
collar.
The inner altitude spring
case is heid
in place on the friction collar by three adjust-
able set screws which must be loosened to rotate
the case
the
collar.
The cuter case fits over
the inner
case
and is
held in place with
three
adjustable set
screws.
In order to maintain the
spring
tension
on the springs a fiber friction
ring frictionally engages the flange of
the frict-
ion collar.
The tension of the friction ting is
regulated by two leaf springs called friction ad-
Justing springs,
one on
the top and
one on the
bottom of the friction ring.
The tension of the
leai springs
must be sufficient to hold
the al-
titude knob at
any desired position. Keyed to the
altitude shaft is the high altitude clutch holder
acainst which the low altitude clutch holder con-
tacts
the outer case is rotated clockwise.
continued
rotation of the outer case
in a clock-
wise direction increases the tension of the outer
altitude spring.
The necessary screws and bear-
complete the assembly.
Do not remove outer spring collar in dis-
assembly
or maintenance.
on the telescope
motor and
take minimum and maximum tachometer
readings.
The minimum disc
speed on the M-3 is
117 and
maximum disc
speed is
On the M-6
Series and
up the disc speed is 10l to 593.
A
gear change arrangement
provides for a disc speed
of 101
to 246 plus
1/2 when the shift is
on low
and for a disc speed
of 246 plus or minus
1/2 to 593 when the shift is on high position.
the altitude knob is out of adjustment
proceed as follows.
Always adjust the
inner al-
titude spring tension first. If
the minimum speed
is too slow turn the inner case to maximum stop,
loosen
the three set screws and rotate the case
clockwise.
Tighten
screws,
rotate
to
minimum
stop and
check speed.
Repeat
this
until the cor-
rect speed is attained.
If the minimum speed is
+ 00
fast,
rotate
inner case
ioosen
to
minimum stop,
set
screws and
rotate case counter clock-
wise until minimum
speed is obtained.
Tighten all
three set
screws; then proceed to adjust the outer
sprina
Rotate the outer case clockwise to
increase speed and
counter-clockwise to decrease
speed.
Be sure the set screws are
loosened before
attempting to turn
the case.
Also check the mini-
67