What is a practical way to avoid harmful interference when calling CQ using Morse code or CW?

1. Send the letter "V" 12 times and then listen for a response
2. Keep your CQ to less than 2 minutes in length to avoid interference with contacts already in progress
3. Send "QRL? de" followed by your call sign and listen for a response
4. Call CQ at low power first; if there is no indication of interference then increase power as necessary ✓ Correct answer

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