Key Topic 79: Repair Procedures

Question 1

3-79L1: When soldering or working with CMOS electronics products or equipment, a wrist strap:

A. Must have less than 100,000 ohms of resistance to prevent static electricity.
B. Cannot be used when repairing TTL devices.
C. Must be grounded to a water pipe.
D. Does not work well in conjunction with anti-static floor mats.

Answer 1

A. Must have less than 100,000 ohms of resistance to prevent static electricity.

Question 2

3-79L2: Which of the following is the preferred method of cleaning solder from plated-through circuit-board holes?

A. Use a dental pick.
B. Use a vacuum device.
C. Use a soldering iron tip that has a temperature above 900 degrees F.
D. Use an air jet device.

Answer 2

B. Use a vacuum device.

Question 3

3-79L3: What is the proper way to cut plastic wire ties?

A. With scissors.
B. With a knife.
C. With semi-flush diagonal pliers.
D. With flush-cut diagonal pliers and cut flush.

Answer 3

D. With flush-cut diagonal pliers and cut flush.

Question 4

3-79L4: The ideal method of removing insulation from wire is:

A. The thermal stripper.
B. The pocket knife.
C. A mechanical wire stripper.
D. The scissor action stripping tool.

Answer 4

A. The thermal stripper.

Question 5

3-79L5: A “hot gas bonder” is used:

A. To apply solder to the iron tip while it is heating the component.
B. For non-contact melting of solder.
C. To allow soldering both sides of the PC board simultaneously.
D. To cure LCA adhesives.

Answer 5

B. For non-contact melting of solder.

Question 6

3-79L6: When repairing circuit board assemblies it is most important to:

A. Use a dental pick to clear plated-through holes.
B. Bridge broken copper traces with solder.
C. Wear safety glasses.
D. Use a holding fixture.

Answer 6

C. Wear safety glasses.