Page 219 - Electromechanical Devices and Components Illustrated Sourcebook

Chapter 10 Wire and Conductors 181

Buss Bars protrude up from the surface. Stiff, solid copper wire is sol-
dered to the top of the screws and a circuit can be laid out.
Buss bars are typically used to provide a central distribution Components are then soldered to the wires as necessary. This
point for power or a common ground point. Figure 10-38 type of construction has all but been forgotten, but is still an
shows two of the most common buss bars. The flat bar is simply excellent method to construct prototype and one-off circuits.
a piece of flat copper with a number of studs and mounting Figure 10-40 shows a typical wire and post assembly.
holes. The block and set screw type are commonly found as
neutral/ground strips in power distribution boxes.

14 AWG Solid Wire
Solder Joint
Insulating Base
Brass Screw and Nut
Flat Bar

Terminal

Block and Set Screw

Figure 10-40 Wire and Post Construction
Figure 10-38 Typical Buss Bars

Electrical Construction Methods Solder Strip Construction

There are a number of methods for assembling electrical cir- Electronics of the 40s, 50s, and 60s commonly used solder
cuits. Among these are printed circuit boards, wire and post, strip construction, as illustrated in Figure 10-41. Like wire
terminal strip, buss wire, and point-to-point. The following and post, this type of construction is principally unused today.
provides a brief review of these methods. However, it still remains a good method for prototyping and
one-off circuits.

Printed Circuit Boards

The most common electronic construction method is the use of Solder Strip
printed circuit boards. This is an excellent method for low current
electronics and control circuits. Figure 10-39 shows a typical cir-
cuit board. The insulating board is usually a fiberglass panel with
the conductors and solder pads laminated to its surface.

Sheet Metal Base
Mounting Holes
Conductors
Insulating Board Terminals
Through Pads
Figure 10-41 Solder Strip Construction

Lead Wire Construction
Edge Pads
Figure 10-39 Printed Circuit Board Lead or buss wire construction is a type of free form assem-
bly. Components are soldered together using only the lead
wires. For obvious reasons the method is also referred to as
The Wire and Post Construction ball construction. After the circuit is complete and tested, it is
generally potted into some sort of case. This produces a special
Early radio, test, and electrical equipment were principally circuit with the appearance of a production unit, but without
constructed using the wire and post method. This practice the associated tooling costs. Figure 10-42 shows an example
uses an insulating board with a number of brass screws which of lead wire or ball construction.