What is the purpose of the color code used on DMR repeater systems?
The correct answer is A: Must match the repeater color code for access. The color code in DMR (Digital Mobile Radio) repeater systems is a numeric identifier (0-15) that must match between your radio and the repeater for you to access the repeater. It's a form of access control.
Each DMR repeater is configured with a specific color code. Your radio must be programmed with the same color code to communicate through that repeater. If your color code doesn't match, the repeater will reject your transmissions even if you're on the correct frequency and have the right talkgroup programmed. The color code is separate from the talkgroup ID - you need both to be correct.
Exam Tip
DMR color code = Must match for access. Remember: The color code must match between your radio and the repeater. It's an access control feature, not related to frequency or signal strength.
Memory Aid
"**C**olor **C**ode = **C**ontrol **C**onnection (think 'CC = CC' = Control Connection, must match)"
Real-World Application
You want to use a DMR repeater that requires color code 1. You program your radio with color code 1, the correct frequency, and the talkgroup ID. When you transmit, the repeater accepts your signal because the color code matches. If you had programmed color code 2 instead, the repeater would reject your transmissions even though everything else is correct.
FCC Part 97.205Key Concepts
Why Other Options Are Wrong
Option B: Incorrect. The color code doesn't define frequency pairs. Frequency pairs are determined by the repeater's configuration, not the color code.
Option C: Incorrect. The color code doesn't identify the codec. DMR uses a standard codec regardless of color code.
Option D: Incorrect. The color code isn't about signal level requirements. It's an access control identifier.
题目解析
The correct answer is A: Must match the repeater color code for access. The color code in DMR (Digital Mobile Radio) repeater systems is a numeric identifier (0-15) that must match between your radio and the repeater for you to access the repeater. It's a form of access control. Each DMR repeater is configured with a specific color code. Your radio must be programmed with the same color code to communicate through that repeater. If your color code doesn't match, the repeater will reject your transmissions even if you're on the correct frequency and have the right talkgroup programmed. The color code is separate from the talkgroup ID - you need both to be correct.
考试技巧
DMR color code = Must match for access. Remember: The color code must match between your radio and the repeater. It's an access control feature, not related to frequency or signal strength.
记忆口诀
**C**olor **C**ode = **C**ontrol **C**onnection (think 'CC = CC' = Control Connection, must match)
实际应用示例
You want to use a DMR repeater that requires color code 1. You program your radio with color code 1, the correct frequency, and the talkgroup ID. When you transmit, the repeater accepts your signal because the color code matches. If you had programmed color code 2 instead, the repeater would reject your transmissions even though everything else is correct.
错误选项分析
Option B: Incorrect. The color code doesn't define frequency pairs. Frequency pairs are determined by the repeater's configuration, not the color code. Option C: Incorrect. The color code doesn't identify the codec. DMR uses a standard codec regardless of color code. Option D: Incorrect. The color code isn't about signal level requirements. It's an access control identifier.
知识点
DMR, Color code, Repeater access, Digital radio
Verified Content
Question from official FCC Technician Class question pool. Explanation reviewed by licensed amateur radio operators.