Confidence: Medium · Source: FCC ULS · As of 2026-09-14
K4AID callsign genealogy
Currently held by BROCK, JAMES D
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 K4AID's current licensee, walking backwards.
- Szwak, DonaldFLgranted 2024-11-16cancelled 2026-03-21
Successor callsigns
Callsigns held now by people who previously held K4AID.
- Brock, James DTNgranted 2022-02-15
All historical holders
Every license row we've seen with the callsign K4AID, oldest first.
- BROCK, JAMES D TN2013-12-13 → cancelled 2022-02-15
- Szwak, Donald FL2026-03-21 active