Updated: Dec 9, 2025 | Source: 2024-2028 Question Pool | Topic: E1F
E1F09E1F

Which of the following cannot be transmitted over an amateur radio mesh network?

Deep Dive: E1F09

The correct answer is C: Messages encoded to obscure their meaning. Which of the following cannot be transmitted over an amateur radio mesh network is messages encoded to obscure their meaning. Encrypted or encoded messages that obscure meaning cannot be transmitted. For amateur radio operators, this is important for mesh network operation. Understanding this helps ensure legal mesh network operation.

Why Other Answers Are Wrong

Option A: Incorrect. Third party traffic can be transmitted - third party traffic is allowed on mesh networks. Third party traffic isn't prohibited. Option B: Incorrect. Email can be transmitted - email is allowed on mesh networks. Email isn't prohibited. Option D: Incorrect. Since A and B are not prohibited, 'all of the above' cannot be correct. Only encoded messages are prohibited.

Exam Tip

Cannot transmit on mesh network = messages encoded to obscure their meaning. Think 'M'esh 'N'etwork = 'M'essages 'N'ot encoded. Encrypted or encoded messages that obscure meaning cannot be transmitted. Not third party traffic, not email - just encoded messages.

Memory Aid

Cannot transmit on mesh network = messages encoded to obscure their meaning. Think 'M'esh 'N'etwork = 'N'o encoding. Encrypted or encoded messages that obscure meaning cannot be transmitted. Important mesh network restriction.

Real-World Example

An amateur radio mesh network: You can transmit third party traffic and email over the mesh network. However, you cannot transmit messages encoded to obscure their meaning (encrypted messages). All amateur communications must be in the clear (except space telecommand). This is the restriction - encoded messages cannot be transmitted on mesh networks.

Source & Coverage

Question Pool: 2024-2028 Question Pool

Subelement: E1F

Reference: FCC Part 97.113

Key Concepts

Amateur radio mesh network Messages encoded to obscure meaning Encryption Mesh network restrictions

Verified Content

Question from the official FCC Extra Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the E1F topic.