Confidence: Medium · Source: FCC ULS · As of 2026-09-14
NK4O callsign genealogy
Currently held by STOCKTON IX, ANDREW J
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 NK4O's current licensee, walking backwards.
- STOCKTON IX, ANDREW JFLgranted 1997-09-09cancelled 2002-05-03
Successor callsigns
Callsigns held now by people who previously held NK4O.
- BISCHOFF, WILLIAM SFLgranted 2000-03-28cancelled 2005-08-22
All historical holders
Every license row we've seen with the callsign NK4O, oldest first.
- BISCHOFF, WILLIAM S FL1995-11-30 → cancelled 2000-03-28
- STOCKTON IX, ANDREW J FL2022-02-08 active