DIRECTIONS: Answer these self-review questions after you have viewed the video and read the handout on soldering. Check your answers in the back of the handout.
1. Solder is the still the finest joining method in electronics. It provides a strong ______________ connection and a low resistance ________________ connection.
2. The process where solder mixes with molecules of a metal surface is called ______________.
3. Solder has ____________ ____________ to current flow. This is especially important in ____________ ____________ applications.
4. Solder is an alloy of ____________ and ____________.
5. Solder has a melting point which is ________________ than either of the two metals from which it is made.
6. What is the melting point of 50/50 solder? __________________
7. The melting point of 63/37 solder is ___________. The melting point of 60/40 solder is ____________.
1. Besides solder, ______________ is an essential ingredient in soldering good connections.
2. ______________ and ______________ collect on air-exposed surfaces, making "wetting" impossible until surfaces are cleaned.
3. Flux must be ________________ before it will clean the surface.
4. There are two types of flux. _______________ is NOT acceptable for electronics work because it is electrically conductive. ______________ flux is the type that should be used for electronics work.
5. Rosin flux is corrosive at ____________ temperature. It is non-corrosive at _____________ temperature.
6. A convenient flux available which is actually a part of solder itself. For electronics work, this is called ____________ ____________ ____________.
7. The first part to melt in rosin core solder is the ___________.
8. For frequent electronics soldering, a soldering gun has two major disadvantages. The trigger action requires time to ___________ the tip and the heat developed is ___________ for electronics.
9. You should use a soldering iron rated at ____________ to ____________ watts for soldering electronic circuits.
10. The main advantages of the soldering iron are that the tip is the right size and the _____________ developed is not excessive for delicate circuits.
11. The tip of the iron should be cleaned on a wet ____________ or ___________.
12. After cleaning, the tip should be _______________ with a layer of solder. This prevents air from reaching the tip and forming ___________.
13. A clean iron makes soldering faster because it transfers ____________ more effectively.
1. A bad solder connection is often called a _________ ____________ _________ .
2. Two common mistakes can cause a bad solder connection. One mistake is not applying enough ____________. The other is allowing the wire lead to ___________ while the solder is cooling.
3. A cold solder connection has a _____________ appearance. It may __________ when under strain.
4. Another bad connection can result if the the rosin is not heated enough to boil away. This mistake is called a _______________.
5. The two most serious problems caused by a cold solder joint are a ___________ physical connection and an electrical connection of ________ resistance.
6. The appearance of a good connection is __________ and ___________ .
7. To achieve a good solder connection, _________________ the component lead to a terminal so it does not ______________ .
8. When soldering a component to a circuit board, leave room in the wire leads for _____________ _____________ .
9. Place the soldering tip against both the wire lead and the _______________ so that both are about the same ____________ .
10. Be sure you see a small amount of ______________ as the rosin ________________.
11. If you are soldering delicate components, use a ________________.
12. Soldering to a flat surface is more difficult than soldering to a terminal because there is no way to _______________ the work. This is called ____________ soldering.
1. Most modern electronics are assembled on ____________ _____________ . While they can be made by machine, they can only be repaired by _____________.
2. One problem in soldering on a ___________ ___________ is that the components and circuit paths are very ______________ .
3. When you are soldering a circuit board, use an iron with a _____________ tip, a ______________ of solder and use as ______________ solder as possible.
4. Because circuit board components are small, they are also _____________ - sensitive.
5. The adhesive that holds copper foil to a circuit board can be damaged by ____________. If this happens, the foil can tear away from the board.
6. ____________ _____________ is a mistake caused by using too large a soldering tip or too much solder on a circuit board.
7. The first step in repairing a poor soldered connection is to ______________ all the solder.
8. A simple repair tool that uses air suction is called a ___________ ____________ .
9. A more sophisticated tool has a vacuum tip integrated as part of the _____________ ___________ .
10. An even more sophisticated tool has a vacuum tip integrated as part of the ____________ _____________.
11. The cleanest and safest unsoldering method for electronics is to use braided wire coated with ____________ flux.
12. When it is __________, the flux cleans the braid. Melted solder flows into the braid by _____________ action.