Confidence: Medium · Source: FCC ULS · As of 2026-09-12
W4SDI callsign genealogy
Currently held by Geno, Nathan C
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 W4SDI's current licensee, walking backwards.
- Geno, Nathan CALgranted 2022-04-06cancelled 2023-01-28
Successor callsigns
Callsigns held now by people who previously held W4SDI.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign W4SDI, oldest first.
- CHEYNEY, BETTY J FL1997-07-23 → cancelled 2009-07-24
- Geno, Nathan C AL2023-01-28 active