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Confidence: Medium · Source: FCC ULS · As of 2026-09-12

WA5ZOO callsign genealogy

Currently held by Yarbro, Mark S

The FCC publishes a previous_call_sign on every amateur license — a self-link to the licensee's prior callsign. Following those links produces the chain below.

Previous callsigns

Older callsigns held by WA5ZOO's current licensee, walking backwards.

  1. KF5TSXcancelled· T
    Yarbro, Mark STXgranted 2013-02-07cancelled 2013-03-01

Successor callsigns

Callsigns held now by people who previously held WA5ZOO.

No current licensee on record previously held this callsign.

All historical holders

Every license row we've seen with the callsign WA5ZOO, oldest first.

  • HERNDON, HAROLD L OK
    1996-05-09 → cancelled 2008-05-10
  • Yarbro, Mark S TX
    2013-03-01 → cancelled 2025-03-05