Which of the following types of solder should not be used for radio and electronic applications?
The correct answer is A: Acid-core solder. Acid-core solder should not be used for radio and electronic applications. Acid-core solder contains an acid flux that is corrosive and can damage electronic components, circuit boards, and connections over time. The acid residue left after soldering continues to corrode, causing failures. For amateur radio operators, only rosin-core solder (or water-soluble flux for some applications) should be used for electronics work. Acid-core solder is for plumbing and other non-electronic applications where the corrosive flux helps clean metal but won't damage the work.
Exam Tip
Acid-core solder = NOT for electronics. Think 'A'cid-core = 'A'void in electronics. The acid flux is corrosive and damages components. Use rosin-core or lead-free solder for electronics.
Memory Aid
"Acid-core solder = Avoid in electronics. Think 'A'cid-core = 'A'void. Corrosive flux damages electronic components. Use rosin-core or lead-free solder for electronics work."
Real-World Application
You use acid-core solder to repair a circuit board. The acid flux cleans the connection well initially, but over time the acid residue corrodes the copper traces and component leads, causing the circuit to fail. Using rosin-core solder would have been safe - the rosin flux is non-corrosive and designed for electronics. Acid-core is only for plumbing.
Key Concepts
Why Other Options Are Wrong
Option B (Lead-tin solder): Incorrect. Lead-tin solder (typically 60/40 or 63/37) is commonly used in electronics, though lead-free alternatives are now preferred for environmental reasons. It's safe for electronics.
Option C (Rosin-core solder): Incorrect. Rosin-core solder is the standard for electronics work. The rosin flux is non-corrosive and safe for electronic components.
Option D (Tin-copper solder): Incorrect. Tin-copper solder is a lead-free alternative that's safe for electronics. It's commonly used in modern electronics manufacturing.
题目解析
The correct answer is A: Acid-core solder. Acid-core solder should not be used for radio and electronic applications. Acid-core solder contains an acid flux that is corrosive and can damage electronic components, circuit boards, and connections over time. The acid residue left after soldering continues to corrode, causing failures. For amateur radio operators, only rosin-core solder (or water-soluble flux for some applications) should be used for electronics work. Acid-core solder is for plumbing and other non-electronic applications where the corrosive flux helps clean metal but won't damage the work.
考试技巧
Acid-core solder = NOT for electronics. Think 'A'cid-core = 'A'void in electronics. The acid flux is corrosive and damages components. Use rosin-core or lead-free solder for electronics.
记忆口诀
Acid-core solder = Avoid in electronics. Think 'A'cid-core = 'A'void. Corrosive flux damages electronic components. Use rosin-core or lead-free solder for electronics work.
实际应用示例
You use acid-core solder to repair a circuit board. The acid flux cleans the connection well initially, but over time the acid residue corrodes the copper traces and component leads, causing the circuit to fail. Using rosin-core solder would have been safe - the rosin flux is non-corrosive and designed for electronics. Acid-core is only for plumbing.
错误选项分析
Option B (Lead-tin solder): Incorrect. Lead-tin solder (typically 60/40 or 63/37) is commonly used in electronics, though lead-free alternatives are now preferred for environmental reasons. It's safe for electronics. Option C (Rosin-core solder): Incorrect. Rosin-core solder is the standard for electronics work. The rosin flux is non-corrosive and safe for electronic components. Option D (Tin-copper solder): Incorrect. Tin-copper solder is a lead-free alternative that's safe for electronics. It's commonly used in modern electronics manufacturing.
知识点
Solder types, Acid-core solder, Electronic soldering, Component protection
Verified Content
Question from official FCC Technician Class question pool. Explanation reviewed by licensed amateur radio operators.