Confidence: Medium · Source: FCC ULS · As of 2026-09-14
W4YCO callsign genealogy
Currently held by Shields, John
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 W4YCO's current licensee, walking backwards.
- Shields, JohnALgranted 2025-07-03cancelled 2025-07-25
Successor callsigns
Callsigns held now by people who previously held W4YCO.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign W4YCO, oldest first.
- CRISWELL, F A AL1996-08-08 → cancelled 2008-08-09
- Shields, John AL2025-07-25 active