Confidence: Medium · Source: FCC ULS · As of 2026-09-14
AJ4UO callsign genealogy
Currently held by Schauwecker, John C
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 AJ4UO's current licensee, walking backwards.
Successor callsigns
Callsigns held now by people who previously held AJ4UO.
No current licensee on record previously held this callsign.