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What does the ham radio term picket fencing mean?

Rapid flutter on mobile signals caused by multipath.

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  1. Rapid flutter on mobile signals from multipath ✔
  2. Taking turns transmitting in a net
  3. A ground system for vertical antennas

Why: When a car moves, it passes through spots where reflected signals add and cancel. The result is a fast flutter, like running a stick along a fence.

Huh, didn't know that: Picket fencing comes from multipath, the same effect that changes signal strength when an antenna moves a few feet.

The dad joke
My radio started picket fencing. Now it wants a white one with a gate.
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References

Answer: Rapid flutter on mobile signals from multipath. When a car moves, it passes through spots where reflected signals add and cancel. The result is a fast flutter, like running a stick along a fence.

  1. ARRL Contest Update, January 7, 2026 www.arrl.org/contestupdateissue?issue=2026-01-07
    Picket Fencing: Rapid flutter on mobile signals due to multipath propagation.
    Checked 2026-10-09.

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