Confidence: Medium · Source: FCC ULS · As of 2026-09-14
K9TJU callsign genealogy
Currently held by ROBERTSON, WILBUR E
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 K9TJU's current licensee, walking backwards.
- Schondelmayer, Daniel CINgranted 2016-09-15cancelled 2017-04-25
Successor callsigns
Callsigns held now by people who previously held K9TJU.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign K9TJU, oldest first.
- ROBERTSON, WILBUR E IN1996-01-31 → cancelled 2008-02-01
- Schondelmayer 258, Dan C IN2017-04-25 active