Confidence: Medium · Source: FCC ULS · As of 2026-09-14
KP4JPA callsign genealogy
Currently held by CASTILLO, LIBORIO (OLIVO)
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 KP4JPA's current licensee, walking backwards.
Successor callsigns
Callsigns held now by people who previously held KP4JPA.
No current licensee on record previously held this callsign.