RCA 73-B Series User manual
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DESCRIPTION
Appficatio
■
The
RCA
Type
73-B Professional Recorder
is
de-
signed
to
make
high-quality disc recordings
at
either
33¼
or
78 revolutions
per
minute
.
It
may
be
used
in
applications
for
preparing
masters
from
which
large
numbers
of
records
can
be
made.
The
recorder
is
highly
suitable
for
broadcastingstations
in
record-
ing
programs
for
use on
future
broadcasts,
for
re-
hearsals, auditions
and
similar
applications.
T
■
r
■
table
The
turntable
of
the
recorder is 17½ inches
in
diameter
and
will
accommodate
blanks
up
to
18
¼
inches
in
diameter
and
¾-inch
thick. A removable
rubber
mat
on
the
turntable
provides a
good
record
base
and
may
be
easily cleaned.
Near
the
center
of
the
turntable
a
drive
pin
is
mounted
over
which
6u
any
one
of
three drive holes
in
the
record blank.
When
it
is
desired
to
make
use
of
record
blanks
without
drive
holes,
this
drive
pin
may
be
pressed
down
so
that
it
will
be
below
the
surface
of
the
rubber
mat
. A plunger-release
button
is
mounted
alongside
the
drive
pin
,
and
when
this
button
is
pressed,
the
drive
pin
comes
back
into
position.
Turatable Drive
The
turntable
is rim-driven
by
two
~ncbronous
motors coupled
to
drive
wheels.
Both
motors
are
1
controlled
by
one
ON-OFF
lever
which
operates a
motor
switch
.
When
the
leveris
turned
OFF,a
brake
automatically is applied
to
the
rim
of
the
turntable,
bringing
it
quickly
to
a stop.
The
motors
are
doubly
rubber
shock-mounted
from
the
motor
board
.
Feed
Screw
a
■
d
Drive
The
feed screw is designed so
that
the
recorder•
bead carriage may
be
used
for
either
ouujde-in
or
inside-out recordings
without
changing
feed screws.
The
feed-screw
drive
consistS
of
a pulley-and-belt
system between
the
drive
shaft
and
turntable
spin-
dle.
Mounted
on
the
drive
shaft
above
the
turntable
is a
friction
wheel
which
drives a flange
on
the
end
of
the
feed screw.
The
friction wheel may
be
moved
up
and
down
over
the
entire
diameter
of
the
flange
by means
of
a
knob
on
the
outside
of
the
drive-shaft
housing
.
This
adjustment selects
the
recording
pitch
and
the
direction
of
cut.
An
muminated
pointer
and
scale
on
the
ouuide
of
the
drive
-
shaft
housing indi-
cates
the
setting
of
lines
per
in
ch for
both
inside-out
and
outside-
in
recordings. A release lever mounted
at
the
top
of
the
housing
disengages
the
friction
wheel
fr
om
the
fl
ange
when
turned
counterclock-
wise to facilitate adjustment to
the
des
ir
ed
number
of
lin
es
per
in
ch.
A
s
pring
attached
to
the
friction
wheel is adjusted at
the
factory
to
provide
the
proper
pressure
against
the
flange
when
the
release lever
is
in
the
eng
aged
po
sition (
turned
clockwise
).
TECHNICAL
DATA
Power Supply Required
lOS
to
l2S volts
60
cycles
(MI
-11825)
SO
cycles (
Ml
-1182
6)
Turntable-drive
motors
. . • . . • . . . . . . . . 8S watts
Pilot
Lamps . . . . . . . . . . . . • . . . . . . . . . . S
watts
Total
Spinllin1
motor
(w
hen
operatin1)
Turntable Speeds
33¾
or
78
rpm
(±½%
)
Turntable Diameter
90
watts
1
4S
watts
17½
in
ches
(
for
blanks
up
to
18¼ -inch di
ameter
and
¾I
-
inch
thick
)
T
■
r
■
table
Speed Re9ulatlon
(wows)
0.2%
(
peak
to
peak
)
at
78
rpm
0
.4%
(peak
to
peak)
at
33¼
rpm
0.0
7%
(
rms)
at
78
rpm
0.14% (
rms
)
at
331
,~
rpm
Recordln9 Pitch
Continu
ous
ly
variable
96
to
152 lines
per
in
ch
with
deten
ts
provided
in
st
eps
of
8 lines
per
inch
.
Direction
of
Feed
Inside-out
or
outside-
in
Dimensions
a
■
d
Wel9H
(a )
Wilh
ubi,ul
Heisht-20
inches
Width-
31¾ inches
Depth
-22¼
inches
Weisht
-280
pounds
(
b)
Wit
ho
ut
~•bir,•I
Heigbt
-2
0 inches
Width
-3
0 inches
Depth
-2
0½
in
ches
N
ote:
See JB-243
40
for
Ml
-11850-C Recorder
Head
technical
data.
IB-24383
www.SteamPoweredRadio.Com
2
Spiralling
A separate self-braking
motor
overdrives
the
feed
screw to
provide
start
and
finishing spirals.
This
motor
is coupled
to
the
feed-screw
drive
shaft
by
a pulley-and-belt system. A non-locking
push-button
switch
near
the
drive-shaft
housing
is
used
to
oper-
ate
this motor.
The
spiralling
pitch
is six lines
per
inch
when
the
turntable
speed is 78
rpm.
For
a
turn-
table
speed
of
33½
rpm
the
spiralHng
pitch
is
re-
duced
in
proportion
to
the
speed change.
Carriage
The
recorder-head carriage is free
to
rotate
about
the
feed-screw
tube
until
a latch locks
the
carriage
with
the
feed-screw
tube
when
the
carriage is
in
the
raised
or
non-cutting position.
When
the
carriage
is raised from
the
cutting
position,
the
feed-nut
arm
automatically disengages
from
the
feed screw;
the
arm
automatically engages
when
the
carriage
is re-
leased
from
the
rest position.
The
center
thumb
nut
on
the
carriage
controls
the
angle
of
the
cut.
The
left-hand
thumb
nut
ad-
justS
the
depth
of
the
cutter.
The
stylus-lowering lever is used
to
raise
or
lower
the
stylus.
When
the
carriage is
in
the
standby posi-
tion
,
the
feed-nut
arm
is engaged,
and
stylus is near
the
surface
of
the
record, ready
to
be
lowered
to
the
record by
operating
this lever.
Recorder Head
The
compensator, transformer, series resistor,
high-off-low switch,
pilot
lamp
and
receptacle
which
are recommended
for
use
with
the
MI-11850-C
Recorder Head
are
all
built
into
the
recorder.
For
a complete description
of
the
Ml-11850-C,
refer
to
the
instruction
book
(IB-24340)
shipped
with
it.
Calibrated
Scales
Four
timing
scales
are
provided, each
calibrated
for 96, 104, 112, 120, 128, 136, 144
and
152 lines
per
inch:
One
for
inside-out
recording
at
33½
rpm,
One
for inside-out
recording
at
78
rpm,
One
for outside-in
recording
at
33½
rpm,
One
for
outside-in
recording
at
78
rpm.
Microscope
A high-quality 36-power microscope
with
an
asso-
ciated
arm
assembly is
provided
for
mounting
along-
side
the
turntable
.
The
microscope scale is calibrated
so
that
each division represents 0.001·
inch
on
the
object viewed.
This
permits
aetual measurement
of
groove and wall
widths
of
the
record face,
and
by
comparison
of
the
dimensions thus
obtained
with
known
standards for
recording
work,
and
with
proper
interpretation,
superior
recordings.
may
be
made.
The
microscope may
be
moved over
the
entire
record surface. A small
lamp
is
mounted
on
the
ad-
justable
arm
to
illuminate
the
record grooves.
An
on-off toggle
switch
for
this
lamp
is
mounted
on
the
microscope
arm.
Transformer
A transformer
mounted
on
the
recorder base sup-
plies
the
power
for
the
pilot
lamps
and
heater
kit.
On
some
of
the
units
two
transformers
a.re
supplied
for this purpose.
INSTALLATION
Unpacking
Take
extreme
care
in
unpacking
and
handling
the
equipment,
with
special
regard
to
the
microscope
assembly.
Prevent
any
dirt
or
foreign
matter
from
entering
the
turntable-spindle bearing.
Connections
Make
all
audio
connections
to
the
TB-2 terminal
board
at
the
front
of
the
recorder.
Connect
the
a-c
power
leads
to
the
TB-1
terminal
board
at
the
rear
of
the
recorder.
Refer
to
the
schematic
and
wiring
diagrams
for
the
proper
terminals
to
be
used (fig-
ures 3
and
4).
Mounting
Mount
the
recorder
on
a
sturdy
flat surface.
Install
the
cabinet
over
the
recorder
using
two
machine screws
and
washers provided. Place
the
turntable
over
the
spindle
carefully.
When
the
cabinet
is
not
used, allow
¼-inch
min-
imum
clearance
around
the
sides
of
the
recorder
to
allow
for floating
of
the
shock
mounting
on
the skid
assembly.
Refer
to
figure 2
for
the
mounting
dimen-
sions
of
the
recorder.
Be
sure
the
four
wood
blocks
on
the
skid
assembly
are
exactly
in
a level
horizontal
plane.
Installing Microscope
Mount
the
microscope-arm assembly
on
the
re-
corder
base
by
means
of
the
threaded
shaft
provided.
Pull
the
two
leads
from
the
microscope
lamp
through
the
opening
on
the
recorder
near
the
threaded
shaft,
and
connect
these leads
to
the
sec-
ondary
winding
terminals
of
transformer
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shown
on
the
wiring
diagram,
figure 4.
(On
those
units
having
two
transformers, connect these leads
to
the
transformer
terminals
which
supply
the
other
lamps.)
Calibrated
Scale
To
install a calibrated scale, place
the
left
end
of
the
scale
(front
view)
over
the
scale
pivot
pin
in
the
end
bracket, pressing
the
scale
and
pivot
to
the
left;
align
the
right
end
of
the
scale
with
the
pivot
pin
in
the
right
support
and
release
the
pressure
to
al-
low
the
pivots
to
engage
the
scale.
Rotate
the
scale
to
secure
the
desired calibration.
To
remove a scale,
press
to
the
left
(front
view)
and
lift
it
out,
right
end
first.
The
scales
are
marked
so
that
the
operator
may
easily
set
the
indicator
for
the
required
length
of
recording.
For
example,
if
a five-minute
recording
is
required,
start
the
cut
with
the
indicator
set
at
5
and
continue
to
cut
until
the
indicator
reaches 0.
Make
certain
that
the
scale
showing
under
the
indicator
agrees
with
the
speed,
direction
of
feed,
and
number
of
lines
per
inch. \
Refer
to
the
instruction
book
on
the
recording
bead
used
for
the
approximate
playing
rime for
the
various numbers
of
lines
per
inch
and
turntable
speeds.
MountinCJ
of
Recorder
Head
Mount
the
MI-11850-C Recorder
Head
on
the
cradle
beneath
the
carriage
casting
using
the
two
thumb
screws furnished
with
the
recorder. Connect
the
recorder-head leads
to
the
plug
as
shown
on
the
schematic diagram, figure
3.
Insert
the
plug
into
the
receptacle
on
the
recorder base.
Automatic
RecordinCJ
Equalizer
A
slit
tube
above
the
feed-screw
tube
is designed
to
mount
an
MI-11100 Automatic
Recording
Equal-
izer.
This
equalizer
is
not
supplied
with
the
recorder,
but
may
be
purchased as
an
accessory.
This
unit
com-
pensates for high-frequency loss as
the
cutter
nears
the
center
of
the
record. A
plug
is
mounted
in
the
right
end
of
the
rear
support
tube
ready
for
connec-
tion
with
the
equalizer.
Wiring
from
this
plug
to
the
terminal
board
is already installed.
Refer
to
the
instruction
book
on
the
equalizer
for
further
com-
plete
installation instructions.
Advance Ball
Kit
To
control
the
depth
of
the
recording
groove
ac-
cuntely,
an
MI-11851 Advance
Ball
Kit
is recom-
5
mended
for use
with
the
MI-11850-C Recorder
Head
when
cutting
wax
discs
or
when
vibration
problems
are
serious.
Suction Nozzle
for
RemovinCJ
Record Shavin91
Fastened
to
the
recorder-head
carriage
is a suction
nozzle
which
terminates just above
the
record.
This
nozzle may
be
connected
to
Recording
Suction
Equipment,
MI-4922,
by
means
of
Hose
and
Cou-
pling
Kit,
MI-4923.
This
method
for
removing
the
shavings
is
especially useful
when
recording from
outside-in
to
prevent
shavings
from
piling
up
ahead
of
the
stylus
and
impairing
its operation.
This
equip-
ment
is
not
included as a
part
of
the
recorder,
but
may
be
ordered
separately.
Pickup and
Arm
A removable
plate
is
provided
on
the
recorder
base
for
mounting
an
MI-11899
Pickup
and
Ann
(not
supplied
with
recorder).
A receptacle
on
t.
be
base is already connected
to
the
terminal board. See
scheruatic
diagram,
figure
3.
A
plug
button
on
the
recorder base covers
an
opening
to
be
used
to
mount
the
arm
rest furnished
with
the
MI-11899.
For
com-
plete
installation instructions,
refer
to
the
instruc-
tion
book
on
the
pickup.
Recommended Associated Equipment
In
addition
to
the
equipment
mentioned
in
the
preceding
paragraphs,
the
following
units may
be
used
with
the
recorder:
1. Orthacoustic Equalizer, MI-4916
2.
Sapphire
Stylus (90-degrees), MI-4878-C
3.
Sapphire
Stylus (70-degrees), MI-4842
4. Steel Stylus, MI-4879-A
5.
Amplifier
(Type
82-Cl),
MI-11209-B
6. Amplifier
(Type
BA-4A),
MI-11223
7. Standard
Cutter
Head,
MI-11853
OPERATION
RecordinCJ
Procedure
For
detailed instructions
covering
recording
pro-
cedure
including
microscope use,
refer
to
the
in-
struction
book
on
the
recorder
head
(IB-24340).
Controls Provided
See figure 5 for
the
location
of
the
recording
controls.
Routine Operation
After
all connections
have
been
made
to
external
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'
equipment
in
accordance
with
the
instructions sup-
plied
with
them,
follow
the
procedure
below:
1.
With
the
turntable
platter
stationary, press
plunger-release
button
near
the
center
of
the
turn
-
table
platter
allowing
the
record-drive
pin
to
come
up
into
position.
2.
Place
a
recording
blank
on
the
turntable
so
that
one
of
the
holes
in
the
record fits
over
the
record-drive
pin.
3.
Be
sure
the
stylus is satisfactory
(worn
styli
should
be
reground
or
discarded).
Check
all
styli
for
form
and
cutting
edge
upon
receipt
from
the
vendor.
4.
Turn
ON
the
master
lamp
switch.
5.
Set
the
heater
switch
to
the
desired position.
The
HI
position
short-circuits
the
7-ohm resistor
in
the
recorder-head
heater
circuit
for
quick
warm-
up
or
for
operation
in
ambient
temperatures
be-
tween
40-degrees
and
65-degrees
Fahrenheit.
The
heater-indicator
lamp
is
on
when
this
switch
is
on
HI
or
LOW.
In
the
off
position
(switch
arm
ver-
tical),
the
heater
circuit
is
not
energized,
and
this
lamp
is off.
6.
Turn
on
the
microscope
lamp
switch.
7.
Set
the
speed-shift
control
knob
to
the
desired
speed position.
8.
With
the
feed-screw
drive
release
lever
in
the
disengaged
position
(
turned
counterclockwise),
set
the
lines-per-inch
control
knob
to
the
desired
setting
as
shown
by
the
indicator
on
the
illuminated
scale.
Put
the
release lever
in
the
engaged
position
(turned
clockwise).
9.
Rotate
the
calibrated
scale
to
the
proper
posi-
tion
to
agree
with
the
setting
of
the
speed-shift
knob
and
lines-per-inch
setting.
10.
Turn
ON
the
motor.
11.
With
tfie
recorder
head
in
the
standby
po-
sition, press
the
feed-nut lever
and
slide
the
car-
riage
horizontally
until
it
is
in
the
desired
position
over
the
record. By means
of
the
stylus-lowering
lever, lower
the
stylus
to
the
record.
12.
Set
the
correct
depth
and
angle
of
cut
by
the
two
knobs
atop
the
carriage.
13.
Keep
the
input
signal
at
the
proper
strength
throughout
the
recording.
14.
To
cut
a
spiral
for
beginning,
ending,
or
separating
portions
of
a
recording,
press
the
spi-
7
railing
switch.
Do
not
use
the
spiralling
motor
con-
tinuously
for
any
length
of
time
other
than
to
cut
the
necessary spirals
on
the
record.
15.
At
the
conclusion
of
the
recording, raise the
stylus-lowering lever
which
lifts
the
recorder head
from
the
record;
then
raise
the
carriage
until
it
locks automatically
in
the
rest position.
16.
Turn
OFF
the
motor
,
and
press
the
lever
firmly
to
stop
the
turntable. Remove
the
record.
CAUTION:
When
the
ruorder
is
nol
being
used,
c11re
should
be
laleen
lo
see
that
the
motor
lever
and.
switches are OFF and.
the
feed-screw
dri
ve lever is
in
the
disengaged
position
(
turned
cou"'ercloclewise).
MAINTENANCE
Four
wrenches
are
provided
to
disassemble
the
recorder
for
servicing.
Lubrication
instructions
are
given
in
the
following
paragraphs.
Tarntable-Drlve Motors
Two
oil
holes
are
provided
in
each
drive
motor
(one
in
each
end
bell)
for
the
lubrication
of
the
motor
bearings. Use a
light
high-grade, non-gum-
ming
machine
oil,
such
as SAE-10.
Put
six
or
seven
drops
in
each
oil
hole
at
intervals
of
one
month.
Each
oil
bole
is covered
with
a
ball
and
spring
seal
to
keep
out
dirt
and
dust.
To
gain
access
to
the
oil
holes, first remove
the
cabinet
Use
an
oiler
with
a
½6-inch
(maximum)
spout.
This
lubrication
may
be
most
easily accomplished
from
the
front
and
rear
of
the
recorder.
Turntable Spindle and Spindle Bearln9
To
lubricate
the
turntable
spindle
and
bearing,
use
petroleum
jelly.
Corria9e Drive-Shaft Bearln9s
To
lubricate
the
carriage
drive-shaft
bearings
use a non-fluid
oil
such
as
"N.
Y.
and
N.
J.
Lubri-
cant
Co.
Type
K-00
Special
Grapbited"
(RCA
dwg.
183440-11).
NOTE
:
Do
not
lubricate
the
cauiage
support
tube
or
the
feed
screw
.
If
these
pam
become
dusty
or
dirty
,
wipe
them
off
with
a
dean
dry
rag
frtt
from
lint.
Replacement Ports
The
following
parts
list
is included
to
provide
identification
when
ordering
replacement parts.
Or-
der
from
"
RCA
RepltUemn11 Paris
Deparlmffll,
www.SteamPoweredRadio.Com
8
•
44010
LOIID
MOUNTING
41230
O£PTH
OFCVT
CONTROi. ANGLE
OF
CUT
CONTROL
figure
5-llecording
Control,
FEEO
NUT
DISENGAGING
LEVER
ANO
LATCH
RECOROER
HEAD
I.Cl'WERING
1---...--
LEVER
Jt317
CO
MPtNSATOII
MOTO,.
80A"0
62041
ACC£PTACLt
Figur
e 6-
Main
AnemlJy
---~
-=--=--=--=-~==~
492$3
M
l-II
e2s\.PUULY
49271
M!-11829/
412.4S
BELT
I
www.SteamPoweredRadio.Com
49241
SOCKET
LAMP
43221
SPRING
49230
SH
AFT
49232
SPRING
49158
PULLEY
53233
4
3220
53849
PULLEY
I
',-,$
I
I
'jI-
~
I
ff
--
=-=---jl
-
1-
7
I I '
I l
-t
I I
I l I'
l !i ,j
I II I
I I I I
I .
I
Figure
8- Recorder-Head Drive Aueml:Jy
•
4g
I
90
WHEEL
END
Of
C
OVE.
R
RE.MOVED
43217
RACK
49240
GEAR
49192
COLLAR
49191
HOUSING
43238
BALL
49194
COLLAR
I
www.SteamPoweredRadio.Com
C11mden,
New
Jersey,"
giving
the
"Stock
Number"
and
"Description"
of
the
parts
wanted.
Replacement
parts
supplied
may
be
slightly
different
in
form
or
size
from
the
original
parts
but
wi
ll
be
complete
ly
inte
r
changeable
with
them.
Refer
to
figures 6
through
13
for
the location
of
each
part.
LIST
OF
PARTS
D•smption
Sloe/,
No
Turntable A
ss
embly
Pad
,
rubber
49229
Pin, record-l
atch
49227
Pin, record-latch release;
with
two
washers
432
11
Spring,
record-latch 43208
Spring,
record-latch release
43210
Turntable,
with
rwo
dowel
pins
49228
Spindle A
sse
mbly
Ball,
spindle-thrust
43237
Bearing,
spindle
49234
B@aring,
sp
i
nd
le
thrust-ball
suppo
rt
43242
Cup,
spindle
thrust-beating
suppo
rt
;
with
nut
43243
Pulley, spindle; wi
th
2
set
screws 49236
Spindle
49235
Ma
in A
sse
mb
ly
Belt, feed-screw
drive
49245
Belt,
spiralling
drive
49245
Board,
spiralling-drive
motor
.
49239
Capacitor, 1.75 mf,
50
v
(C3)
53432
Clamp,
capacitor
91577
Compensator
19317
Flange,
pickup
receptacle
53080
Motor,
spiralling
drive
(M-3)
49238
Mounting,
Lord
44090
Plug,
recorder
bead
(J-
l)
52500
Pl
ug
button,
for
pickup-arm
rest
70407
Pulley,
spiral
l
ing
motor;
with
set
screw
(MI-11825) 49253
Pulley,
spiralling
motor;
with
set
screw
(
Ml
-11826) 49276
Receptacle,
pickup
arm
(J-6)
53082
Receptacle,
recorder
head
(J-2)
52401
figure 9-TurntalJe Aueml:Jy
11
49234
BEARING
492.35
~PINOI.E
49236
PULLEY
432.37
BALL
432.42
BEARING
43243
CUP
Figure
JO-Spindle
,U,emhly
D•seript
ion
S10,lt
No.
Screw,
pivot,
for
feed•screw drive;
wi
th
hex
nut
49247
Sp
ri
ng
,
strap,
for
mounting
pickup
recepcacle 53081
Switch,
spiralling
motor
(S-
3)
43173
Ba
se A
ss
embly
Arm,
brake
49264
Arm,
idler
pulley
70278
Arm,
speed-shift
43290
Br
ake
assembly 49263
Bushing,
fo
r leads
49268
Capacitor, 1.75
mf
,
330
volt
(C-
1,
C2)
49275
Cover,
front,
for
motor
and
drive
49243
Cover,
rear,
for
motor
and
drive;
with
brace
49242
Grommet,
tra
n
sformer
support
16058
Knob,
speed-shift 49274
Lamp
,
heater
indicator,
Mazda
5l
or
equival
e
nt
(
A-3)
11765
Lever,
for
front
id
l
er
pulley
49258
Lever,
for
rea!
idler
pulley
49272
Lever,
on
and
off
4926
1
Motor
,
50
cycle, Ml-11826 (M-1, M-2) 49277
Motor
,
60
cycle.,
MI
-11825 (M-1,
M-
2)
49255
Mounting,
Lord,
for
motors
49256
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12
..
492
1$ M
IC
R
OSCOPt
49
21
8
ARM
492
19 SOCl<£T
P-n335
t
Figure
11-Microecope
and
Ann AuemlJy
49
1
77
SPRING
49173
SPRING
,
~
49172
STUD
49
17
5 SH
AF
T
49185
SPRING 49171 FEED
NUT
49203
CARRIAGE
49199
ARM
49168
PLATE
49196
C
OV
ER
49170
ARM
49174
SPRING
_ _
......,.
49169
PIN
49189
PIN
.
~
49198
BRA
C
KET
49197
BRACKET
,-tTIH4-601
!52972
SCREW
I
Figure 12-Carrias,e AuemlJy
www.SteamPoweredRadio.Com
LIST OF PARTS
(Continued)
Plate,
motor
Pulley.
idler
Base Assembly
(cont.)
Pulley,
motor
,
MI
-11825
Pulley,
motor
, Ml-11826
Resistor, 7
ohm,
5
watt
(R-1)
Screw,
shoulder,
for
idler
-
pulle
y
arm
Screw, s
houlder,
for
on
-
and
-o
lf
lever
Screw, shoulder,
for
slide
Slide,
idler
-pulley disengaging
Spring, friction-drive tension
Spring, slide
Spring
, speed-
shift
arm
Switch, beater,
three
position
(S-4)
Switch, master,
for
all
lamps
(S-1)
Switch,
power
,
for
drive
motors
(S-2)
Transformer
(T-1) (complete
replacem
e
nt
unit
for
one
or
two
tran
s
formers)
Recorder-Head Drive Assembly
Ball
,
dutch
Collar,
lower
drive
shaft;
with
two
set
screws
Collar,
upper
drive
shaft;
with
two
set
screws
Outch;
less
spring
and
ball
Gttr,
pitch-change;
with
set
screw
Housing,
dutch
;
with
two
let
screws
Indicator,
pitch
Lamp,
pilot,
pitch-change,
Mazda
44
or
equivalent (A-2)
Pulley, assembly, spiralling-drive
Pulley, feed-screw
drive
Rack, pitch-change
gear
Shaft, pitch-change;
with
knob,
collar,
groove
pin,
and
spring
Socket, pitch-
change
pilot
lamp
Spring
,
dutch
Spring
, pitch-change
knob
Spring, pitch-change
locking
Wheel,
friction-drive
Microscope and
Arm
Assembly
Arm,
lower,
microscope
Arm,
microscope
pilot
lamp
Arm,
upper
, microscope
Bearing, microscope-arm
thrust
Bracket, microscope
Lamp,
pilot,
Mazda 51
or
equivalent
(A
-
1)
Microscope
Nut,
cap;
for
upper
microscope
arm
shaft
Nut,
cap; microscope adjustment-shaft
Nut,
thumb
, microscope
Pin,
microscope
thumb-nut;
with
groove
pin
Shaft,
lower
microscope arm
Shaft, microscope
adjustment
Shaft,
upper
microscope
arm
Stod,
No
49254
49257
49260
49278
52567
49265
49267
49266
49259
53321
43905
49262
52498
49273
41592
52400
43238
49194
49192
53
23
3
49240
49191
49246
11765
53849
49158
43217
49230
49241
43220
49232
43221
49190
49216
49218
49217
49222
49220
44887
49215
49225
33134
49208
49223
49244
49226
49221
..
D~smt,liO#
Socket, microscope
pilot
lamp
Switch, microscope
pilot
lamp
(S-5)
Washer
,
spring,
microscope
pilot
lamp
Carriage Assembly
Arm,
carriage-lift
Arm,
feed-nut
support;
with
2
aet
screws
Bracket,
recorder
-
bead
support;
with
pin
Bracket,
slide
Carriage
and
bushing
;
with
pin
Cover,
carriage
Feed
nut
Pio,
feed-
nut
arm
support
Pin
, feed-nut disengaging
Plate
,
carriage
back
-
support
Screw,
thumb,
to
mount
recorder
head
Shaft, recorder-head
lift
Spring, feed-nut
engaging
Spring
, friction
Spring, la
tch
Spring,
slide
suppon
Stud,
shoulder,
latch
Carriage Drive Assembly
Bearing, ball,
for
feed
screw
Button,
plug
,
for
end
housing
Cam,
drive
-
head
disengaging,
with
let
screw
Oamp,
suction
tube
Collar,
end
bracket
feed screw;
with
set
screw
Guide,
left;
with
two
machine screws
Guide,
right;
with
two
machine screws
Indicator
, carriage position
Lever, feed-nut disengaging
Lever,
drive
-
head
disengaging; with
two
sec
screws
Lever, stylus
lowering
Nut,
thumb,
for
depth
and angle adjusuneocs
Pio
, end-bracket time-scale
support
Pin,
time-scale
support
Plug
,
for
connection
to
equalizer
Post, drive-
head
spring
Scale, pitch-indicator
Scale, recording-time, 96, 104, 112, 120-78
Scale,
recording
-time, 128, 136, 144, 152-78
Scale, recording-time,
96.
104, 112, 120-33¾
Scale,
recording
-time, 128, 136, 144, 152-33¾
Screw, feed;
with
flange
Screw, pivot,
recorder
head
Spting
,
depth
adjustment
Spring
,
drive
-
head
engaging
Spring,
end-bracket time-scale support
S
pring
, slide
tightening
Stud,
depth
adjustment
Tube,
suction,
shaving
remover
Was
her
,
spring,
end-bracket time-lc:ale
suppon
B
S1od1No
49219
48791
49224
49199
49170
49198
49197
49203
49196
49171
49189
49169
49168
52972
49175
49174
49185
49173
49177
49172
49139
491S5
49212
49210
49160
49201
49202
49154
49166
49213
49167
49204
49151
49162
53320
49211
49207
49249
49250
49251
49252
49195
48018
49205
49214
49152
19716
49187
49209
3lti08
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