Deep Dive: E2E05
The correct answer is A: WSPR. Which of these digital modes does not support keyboard-to-keyboard operation is WSPR. WSPR is a beacon mode, not interactive. For amateur radio operators, this is important for understanding digital modes. Understanding this helps when selecting digital modes.
Why Other Answers Are Wrong
Option B (RTTY): Incorrect. RTTY supports keyboard-to-keyboard operation - WSPR doesn't. RTTY supports it. Option C (PSK31): Incorrect. PSK31 supports keyboard-to-keyboard operation - WSPR doesn't. PSK31 supports it. Option D (MFSK16): Incorrect. MFSK16 supports keyboard-to-keyboard operation - WSPR doesn't. MFSK16 supports it.
Exam Tip
Digital mode without keyboard-to-keyboard = WSPR. Think 'W'SPR = 'W'eak 'S'ignal 'P'ropagation 'R'eporting (beacon, not interactive). WSPR is a beacon mode, not interactive. Not RTTY, not PSK31, not MFSK16 - just WSPR.
Memory Aid
Digital mode without keyboard-to-keyboard = WSPR. Think 'W'SPR = 'B'eacon mode. WSPR is a beacon mode, not interactive. Important for understanding digital modes.
Real-World Example
Digital modes: RTTY, PSK31, and MFSK16 all support keyboard-to-keyboard operation - you can type messages back and forth. WSPR is different - it's a beacon mode that just transmits your call sign, location, and power level. There's no keyboard-to-keyboard operation with WSPR. This is the mode - WSPR doesn't support keyboard-to-keyboard operation.
Source & Coverage
Question Pool: 2024-2028 Question Pool
Subelement: E2E
Reference: 2024-2028 Question Pool · E2 - Operating Procedures
Key Concepts
Verified Content
Question from the official FCC Extra Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the E2E topic.