Morse Code in Amateur (Ham) Radio

Morse Code in Ham Radio

Despite being nearly 200 years old, Morse code (known as CW or Continuous Wave in ham radio) remains one of the most popular operating modes in amateur radio. Many operators choose CW not out of necessity, but because of its unique advantages.

Why CW Is Still Popular

1. Signal efficiency: A CW signal occupies only about 150 Hz of bandwidth, compared to 2.4 kHz for SSB voice. This means CW can be decoded at much lower signal levels.
2. Weak signal work: CW can be copied reliably at signal strengths 10–15 dB below what voice requires. This makes it ideal for long-distance (DX) communication.
3. Simple equipment: A CW transmitter can be built from a few components. The simplest ham radio transmitters are CW-only.
4. Universal language: CW abbreviations and Q codes transcend language barriers. Operators who share no common spoken language can have a complete QSO in Morse.

CW Contesting

CW contests are among the most popular ham radio competitions:

• CQ World Wide CW (November): The largest CW contest
• ARRL Sweepstakes CW (November): Major North American contest
• CQ WPX CW (May): Worldwide prefix contest

Contest operators often send at 30–40 WPM and can process rapid-fire exchanges.

Licensing Requirements

• USA (FCC): Morse code testing was removed from all license classes in 2007. However, many operators still learn CW voluntarily.
• Japan (JARL): A Morse code proficiency test is still required for some license classes.
• International: Requirements vary by country; the global trend has been toward removing mandatory CW testing.

QRP and CW

QRP (low power, typically 5W or less) operators especially favor CW because of its efficiency. A 5W CW signal can regularly reach across oceans, which would be nearly impossible with 5W of voice.