Confidence: Medium · Source: FCC ULS · As of 2026-09-12
WB4MJ callsign genealogy
Currently held by JUMPER, MICHAEL H
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 WB4MJ's current licensee, walking backwards.
- JUMPER, MICHAEL HSCgranted 2000-12-28cancelled 2005-03-08
Successor callsigns
Callsigns held now by people who previously held WB4MJ.
No current licensee on record previously held this callsign.