Confidence: Medium · Source: FCC ULS · As of 2026-09-14
W9ZBM callsign genealogy
Currently held by Robertson, William 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 W9ZBM's current licensee, walking backwards.
- Robertson, William EWIgranted 2011-01-31cancelled 2017-08-25
Successor callsigns
Callsigns held now by people who previously held W9ZBM.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign W9ZBM, oldest first.
- ROBERTSON, EARL G WI1997-05-15 → cancelled 2009-05-16
- Robertson, William E WI2017-08-25 active