Confidence: Medium · Source: FCC ULS · As of 2026-09-12
K4LOS callsign genealogy
Currently held by MADRID, CARLOS 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 K4LOS's current licensee, walking backwards.
- MADRID, CARLOS JCAgranted 2014-09-25cancelled 2014-10-15
Successor callsigns
Callsigns held now by people who previously held K4LOS.
No current licensee on record previously held this callsign.