4 ms·

Then how do you distinguish between "long" and "two shorts"?

• BenjiWiebe 4y ago
  Timing, I suppose. A double tone with much less than one dit's worth of spacing would be a dah.
• wrycoder 4y ago
  Original Morse telegraph was not done by tones. The sounder emitted two clicks, subtlety different, for each key down/up event. So, a dit would be two clicks with a short interval, while a dah would be two clicks with a longer (3x?) interval.