Confidence: Medium · Source: FCC ULS · As of 2026-09-12
KF4FK callsign genealogy
Currently held by MICKELBERRY, ROBERT A
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 KF4FK's current licensee, walking backwards.
- KEISLING III, FREDERICK CFLgranted 2010-09-27cancelled 2011-04-30
Successor callsigns
Callsigns held now by people who previously held KF4FK.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign KF4FK, oldest first.
- MICKELBERRY, ROBERT A FL1987-09-22 → cancelled 1999-09-23
- KEISLING III, FRED C FL2021-02-05 active