Morse Code for "1" — Pattern, Mnemonic & Audio
·−−−−
1 = ·−−−− (1 dit, 4 dahs)
Mnemonic
one-WORLD-WAR-ONE-WON
Syllable-based memory aid
Timing
1 + 3 + 3 + 3 + 3 units
At 20 WPM: 780ms total
Type
Number
International Morse Code (ITU-R M.1677-1)
Common Words with 1
FIRST194118441912100WPM
Abbreviated Numeral (Cut Number)
·−−−−
Full (5 elements)
→
·−
Cut = A
Cut number: A (·−). The abbreviation saves 3 elements (·−−−− vs ·−). Used extensively in contest and traffic handling.
In Amateur Radio
Appears in signal reports (519 = weak but readable), frequencies (1.8 MHz = 160m band), and RST reports. In cut numbers, 1 becomes A (·−).
In Aviation
Appears in runway designations (Runway 18 = due south), altitudes (FL180 = 18,000 feet), and ILS categories (CAT I, CAT II, CAT III).
In Maritime
Appears in buoy numbers, channel designations, and the SOLAS Chapter 1 requirements for radio equipment.