Red Seal Electrician Practice
Signalling and communicationQuestion 40 of 1506

An 8-bit value is sent once per second. In parallel form, the busiest wire changes at most 0.5 Hz. About what frequency does the single serial wire reach?

  1. About 0.5 Hz
  2. About 4 Hz
  3. About 8 Hz
  4. About 64 Hz
Show answer

Correct answer: About 4 Hz

Eight bits in one second gives about an eightfold increase: 0.5 Hz x 8 = 4 Hz.

Source: Lessons in Electric Circuits IV: Digital (Kuphaldt), 14.4: Electrical Signal Types

Practice signalling and communication

Questions last reviewed: 18 October 2026