A chemical added to the cleaning solution to lower surface tension and to promote wetting.

Surface Tension

The natural, inward, molecular attraction force that inhibits the spread of a liquid at its interface with a solid material.

Surface Mounting

The electrical connection of components to the surface of a conductive pattern that does not utilize component holes.

Surface Leakage

The passage of current over the boundary surface of an insulator as distinguished from passage through its volume.

Surface Insulation Resistance(SIR)

A measure in ohms of an insulating material’s (as in FR-4) electrical resistance between conductors.

Surface Insulation Resistance(SIR)Test

Test for the level of resistance of an insulating material, such as FR-4.between conducting members of a board (traces, contacts).

Supported Hole

A hole in a printed board that has its inside surface plated or otherwise reinforced.

Subtractive Process

A process for obtaining conductive patterns by selective removal of unwanted areas of conductive foil from a metal clad base material.


See Base Material.


A type of transmission line configuration which consists of a single narrow conductor parallel and equidistant to two parallel ground planes.


The deformation resulting from a stress.

Straight-through Lead

A component lead that extends through a hole and is terminated without subsequent forming.


A method by which successive exposures of a single image are made to produce a multiple-image production master.

Step Soldering

The making of solder connections by sequentially using solder alloys with successively lower melting temperatures.

Statistical Process Control(SPC)

The use of statistical techniques to analyse the outputs of processes with the results guiding actions taken to adjust and/or maintain a state of quality control.

Stamped Printed Wiring

Wiring which is produced by die stamping and which is bonded to an insulating base.

Spurious Signal

See Cross-talk.


The highest temperature at which filler metal(Solder) is completely solid.

Solderless Wrap

A method of connecting a solid wire to a square, rectangular, or V-shaped terminal by tightly wrapping the wire around the terminal with a special tool.


A process of joining metallic surfaces with solder, without the melting of the base metals.

1 ... 6 7 8 9 10 11 12 13 14 15 16 ...
Ranking Name Answers
1 J****ire 5
2 PCBWay Support 4
3 p****ard 2
4 Engineer 2
5 vinz 1
6 M****ola 1
7 B****ndu 1
Back to top