Wire wrap-Overview-Custom Design Circuit
Board Electronic Pcb
A correctly made wire-wrap connection for 30 or 28 AWG wire is seven turns (fewer for larger wire) of bare wire with half to one and a half turns of insulated wire at the bottom for strain relief. The square hard-gold-plated post thus forms 28 redundant contacts. The silver-plated wire coating cold-welds to the gold. If corrosion occurs, it occurs on the outside of the wire, not on the gas-tight contact where oxygen cannot penetrate to form oxides. A correctly designed wire-wrap tool applies up to twenty tons of force per square inch on each joint.
The electronic parts sometimes plug into sockets. The sockets are attached with cyanoacrylate (or silicone adhesive) to thin plates of glass-fiber-reinforced epoxy (fiberglass).
The sockets have square posts. The usual posts are 0.025 in (0.64 mm) square, 1 in (25.4 mm) high, and spaced at 0.1 in (2.54 mm) intervals. Premium posts are hard-drawn beryllium copper alloy plated with a 0.000025 in (630 nm) of gold to prevent corrosion. Less-expensive posts are bronze with tin plating.
The 30 AWG Kynar wire is cut into standard lengths, then one inch of insulation is removed on each end.
A "wire wrap tool" has two holes. The wire and 1⁄4 in (6.4 mm) of insulated wire are placed in a hole near the edge of the tool. The hole in the center of the tool is placed over the post.
|Professional Manufactur Custom Design Circuit Board Electronic Pcb|