IBM Selectric Reference Manual

CAM CHART
Contact
N/O Duration
Color
C-l
45°
Blue
C-l
65°
Black
C-2
90°
White
C-2
110°
Orange
FIGURE 46. Cam Chart
KEYLEVER CONTACTS
NOTE:
The contact assembly should be removed from the contact
and stop screw mounting bracket for adjustments 1 & 2.
1. Stop Screw (Fig. 47)
2.
a. Position the mounting bracket (left or right) so that
the stop screws are directly under the keylever.
b. Ad just the keylever stop screws so that the key-
levers do not go further down than the tab key-
lever.
\
\
\
\
t:;~3" Contact and Stop
Screw Mtg. Brkt.
FI GURE 47. Stop Screw
Contact Position (Fi g. 48)
a. Position the contacting actuating springs relative to
the a/pis for vertical al i gnment.
b. Form the N/C contact so that the O/P (at rest) lifts
the N/C contact adequately. In this condition,
check for sufficient O/P to N/O contact air gap.
The N/C contact must break before the N/O con-
tact makes.
NOTE:
Contact assembly must be installed for adjustments.
~
Contact Actuating
.....o::-a---_ Springs
: I N/C Contact
I
I
N/O Contact
FIGURE 48. Contact Position & Air Gap
3.
Contact Assembly Position, unit installed (Fig. 49)
a. Position the contact assembly (left or right) on the
mounting bracket so that the keylevers are center-
ed on their contact actuating springs.
b. With the keylevers held against their stop screws,
position the mounting bracket (front to rear) for
adequate rise of the N/O contacts.
Check the following conditions:
1. The N/C contact must open.
2. Overthrow after the N/O contact makes must
not be great enough to damage the contact
straps.
Center Line
Contact Actuating Spring
Keylever ~,..o--+ill
Stop Screw
r
Contact Spring -----"-
Mtg. Brkt"
Must
Open
4.
O/P
Must Rise:jE
FIGURE
49. Keylever Contact Adjustment
Index Keylever Contacts - Position the contact bracket
so that the alp just touches the index keylever.
KEYBOARD LaC K MECHAN ISM
1.
2.
Switch Link - With the On/Off Switch in the off posi-
tion adjust the switch link so that the On/Off keybutton
matches the slope of the keyboard (Fig. 50).
....... -- Keybutton
On/Off Switch
FIGURE 50. On/Off Switch
Adjusting the link too long can cause the switch to turn
off due to the spring load in the off direction and also
the load from the lockout shaft.
Lockout Bail Link - Position the clevis approximately
half way on the threads of the link (Fig. 51).
2-13

IBM Selectric Specifications

General

Type	Electric typewriter
Introduced	1961
Keyboard Layout	QWERTY
Carriage Return	Electric
Manufacturer	IBM
Printing Technology	Typeball (golf ball)
Power Source	AC Power
Power Supply	120V AC