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RE-COLLECT

Printed Wiring Boards



When assembling an electronic circuit, a board is needed on

which the components can be mounted and wired together. This

board is called a Printed Wiring Board (PWB).

In Japan, the printed wiring board used to be called a "Printed

Circuit Board." Nowadays in Japan the name "Printed Circuit

Board" is not used because the initials of "Printed Circuit Board"

are "PCB." PCB also stands for "Polychlorinated Biphenyls

(PCBs)," which is a poison. So in Japan, we refer to the boards

as "Printed Wiring Boards." In other countries, they are still

refered to as "Printed Circuit Boards," or PCBs.



Making a PWB takes a lot of work, and can be very difficult. For

this reason, for many hand-made circuits, I often use a universal

PWB.

The universal PWB consists of an insulation board drilled with

.8mm holes at 0.1 inch (2.54 mm) intervals. The board is

completely covered with these holes from edge to edge. The

insulation board is comprised of fiberglass (glass epoxy), paper

epoxy, or

bakelite plastic.

Centered around

each hole on the

bottom of the

PWB is an

(approximately)

2mm copper leaf

(known as the

"land" or "pad").



To use the board,

the parts are mounted on the face of the board, and the

component leads are passed through the nearest holes, to project

through the bottom of the board, where the wires can be soldered

together.

The interval between the holes is 0.1 inches (2.54 mm), so DIP

or SIP ICs can

be easily

mounted.



The photograph

shows a PWB

made of glass

epoxy. The color

is green.

Paper epoxy

boards have a

beige color. In

case of bakelite,

the color is thin brown.



As for the size of the board, there are several kinds by the

number of the holes.

From the left side in the photograph

55 x 40 holes (size 160 x 115 mm)

30 x 25 holes (size 95 x 72 mm)

25 x 15 holes (size 72 x 47 mm)



There are various sizes in addition to what I have shown, so you

can select a board according to your needs.

The boards can also be cut to size.



On the top right in the photograph, the back side is shown. The

copper leaf on this board has been pre-soldered ("tinned") to

make soldering easier, so it has a silver color. If the board has

not been pre-soldered, then it is seen to have a copper color.



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