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Pulse dialing waveform for number 401

Short answer

For 401: 4 loop-break pulses for digit 4, inter-digit pause, 10 pulses for 0, pause, then 1 pulse for 1. Each pulse period is 100 ms (break 66.7 ms, make 33.3 ms), inter-digit pause ~200 ms.

Draw the pulse dialing waveform for the number 401.

Each digit is sent as that many loop breaks (0 = 10 breaks) at 10 pulses per second (period 100 ms, break 66.7 ms, make 33.3 ms), with an inter-digit pause between digits.

Loop current (high = make/closed, low = break):
         4 pulses        10 pulses (digit 0)  1 pulse
 ───┐ ┌┐ ┌┐ ┌┐ ┌──────┐ ┌┐ ┌┐ ... ┌┐ ┌──────┐ ┌──────
    └─┘└─┘└─┘└─┘  IDP └─┘└─┘└ ... ┘└─┘  IDP └─┘
     digit 4             digit 0           digit 1
 One pulse = 100 ms: break 66.7 ms + make 33.3 ms
 IDP = inter-digit pause (~200 ms or more)

✓ Answer checked by Claude Opus 5.5 (high effort)

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