Page 84 - Electromechanical Devices and Components Illustrated Sourcebook

46 Electromechanical Devices & Components Illustrated Sourcebook

Dual Banana Plug

Shorting Wire

Banana Jack

Machine Screw
Washer
D
C E
Panel F
COM.
B
A
Insulating Washer
Nut

Output Cable

Grommet

Grommet Cabinet

Input
Wire

Figure 4-31 Jumper Selector Switch Exploded View

Early test and radio equipment commonly used button
selector switches, as shown in Figure 4-32. These switches
offered excellent, low-resistance contacts at a time when
switches were built entirely by the manufacturer of the equip-
ment in which they were used. They are now found almost
exclusively as educational aids.
Figure 4-33 shows a modern, open-frame, multipole,
selector switch. These switches are available in a variety of
configurations, positions, and pole counts. The decks are gen-
erally constructed from fiberglass insulating board with cop-
10
9 11
8 12 Selector per contact inserts. The switch decks are assembled onto the
Leaf 13
Knob main deck with spacers and threaded rods. The main deck
Springs 6 14
5 15
generally carries a detent mechanism that provides position
4 16
accuracy and tactile feedback.
3 17 Brass
2 18 Buttons Figure 4-34 shows a typical enclosed selector switch design.
These units are available with solder and screw terminals.
1 19
High-current selector switches, as shown in Figure 4-35,
Terminals Base
Common 20 typically incorporate some type of snap action mechanism.
These switches are not particularly comfortable to operate.
The actuators are rather stiff and require rotation and loading
Figure 4-32 Button Selector Switch until the mechanism snaps.